Talk:Transistor/Archive 3

Archive 1

Archive 2

Archive 3

Archive 4

History

Talks related to Transistor history and its etymology were moved to talk:Transistor history

This article cites different dates than the Transistor History article. Perhaps all references to specific dates should be left to the Transistor History page itself. Metajon (talk) 18:12, 15 March 2009 (UTC)

Understanding concepts

Substantial gain

Someone asked in the article "what doees substantial gain mean"? I believe the answer is that it means gain that is greater than 1 by an amount sufficient to convince the experimenters that they are observing actual active amplification. It can be voltage ratio or a current ratio or a power ratio, but in general gain is the ratio of output to input, and you don't get gain greater than 1 from electronic components that are passive, or not active. Dicklyon 21:26, 12 November 2006 (UTC)

Perhaps the word "substantial" should be removed then. It's ambiguous and understandably leaves the reader wondering, "how substantial"? -- mattb @ 2006-11-12T21:29Z

What you put in its place to indicate "enough gain that we were sure it was working"? Dicklyon 21:35, 12 November 2006 (UTC)

How about "above-unity gain"? A number of things would work better than "substantial". -- mattb @ 2006-11-12T21:37Z

Or you might want to quote John B. Johnson who used the term "substantial" in decribing his experiment on making a Lilienfeld device. See the section on field effect transistor. Dicklyon 21:38, 12 November 2006 (UTC)

Whatever, if you really want to keep the word I won't make any fuss. I personally believe it is not the best word to use here because it can connotate a large quantity rather than simply meaning considerable/significant/not trivial (though these, too sometimes have the "large" connotation) depending on how the reader takes it. However, I'm not currently on a mission to rewrite this article (my current mission is Computer if you want to take a look), so I'm not too interested in diction debates. :) -- mattb @ 2006-11-12T21:58Z

Bipolar Name

Currently the BJT para says that they are so called because they use both majority and minority carriers. Minority carriers are unwanted leakage (ref Amos). Majority carriers (holes & electrons) are the bits you want. This is what is said about the name from some place on the interweb: "because the controlled current must go through two types of semiconductor material: P and N." I think this is right. - CPES 22:13, 27 April 2006 (UTC) (80.177.169.33)

I don't really understand what you say here. In a bipolar transistor, conduction is done using both type of carriers, electron and holes. Which is minority and which is majority only depends on the type of semiconductor material. I can't see any relation to the leakage current. Have I missed something? - CyrilB 18:48, 22 May 2006 (UTC)

It's too simplified. Actually, see, Bipolar_junction_transistor#Basics_of_transistor_operation, or how it's explained in Russian Wikipedia: Bipolar transistor:

In active mode, voltage is applied to transistor so, that its emitter junction is shifted in forward direction (is open) and collector junction is shifted in reverse direction. For clear explanation, let's consider NPN transistor; all the reasonings are valid for the case of PNP transistor with substituting the word "electrons" for "holes" (and conversely) and also reversing signs of all voltages. In NPN transistor, electrons, the majority carriers in emitter, pass through open emitter-base junction in the region of base. Part of this electrons recombinates with majority carriers in base (holes), part of electrons diffuses back into emitter. However, due to the base is made very thin and (very?) low doped, the main part of electrons, injected from emitter diffuses into region of collector. Strong electric field of reversly shifted collector junction captures electrons (note that they are minority carriers in the base, so the junction is open for them) and carries them in collector. So, collector current practically equals emitter current, except for small loss for recombination in the base, which produces base current (I_e=I_b+I_c). Coefficient α, relating emitter current and collector current (I_c=α I_e) is called "transfer coefficient of emitter current"(????!). The value of coefficient α equals 0.9 — 0.999; the more the coefficient the better the transistor. This coefficient poorly depends on voltages at collector-base and at base-emitter. So in the wide range of operating voltages collector current is directly proportional to base current, the coefficient of this proportionality being equal to β=α/(1-α)=(10-1000). Thus, changing low current of base the considerably larger collector current may be managed.

ellol 22:20, 22 May 2006 (UTC)

Semi-Conductor vs. Conductor

On an atomic level, the difference between a conductor and a semi-conductor is in the number of electrons. Every atom has several orbitals, or paths that an electron follows, going around the nucleus of the atom. Each orbital has a certain maximum capacity of electrons that can follow that path. When an orbital that can only hold five electrons has four electrons and an electric charge gives it two more, it will try to pass one of them on to the next orbital or the next atom. A conductor atom has all of its orbitals full, making it pass on charges easily and without the loss of any electrons. A semi-conductor does not have all of its orbitals full which means that unless a certain minimum charge is sent through it, it will not pass the electrons to the next atom.

My alternative simplification would be that...

On an atomic level, the difference between insulator, semi-conductor and conductor is the energy required to promote an electron into the conduction band. In conductors, no energy is required, each atom is already contributng at least one electron to a "sea" of electrons which slosh about freely in the material. In insulators, a very high energy is required, typically the material has all electrons strongly bound to the atoms and unavailable to move. In semi-conductors, the band gap of the material is such that thermal energy is sufficient that some electrons become available for conduction. The inclusion of impurities or doping with atoms with a different valency provides sites which donate extra electrons or holes (a lack of an electron where one would be expected) to modify the conductivity of the material.

NeilUK 09:23, 6 June 2006 (UTC)

Band gap

"The band gap is highly temperature dependent, decreasing with increasing temperature." part erased: the energy gap is always the same. What changes with temperature is the probability to cross the gap. User: 129.13.186.1

The above correction is from tran history and makes a very good point. I have read that the band gap varies with temperature. It also says this on Wiki band gap, so this needs to be sorted. I have changed the "Semiconductor material" sub section to cover this aspect. CPES 12:38, 25 Apr 2005 (UTC)

The band gap varies with temperature, but very little, and this is an almost insignificant contributor to changing conductivity. As stated above, the most significant factor is the ability of the carriers to cross the gap. Phil Holmes 15:34, 19 August 2005 (UTC)

Proportional current?

Im worried about the phrase 'allows a proportional current to flow'. In fact the current is not proportional to the voltage in a BJT but prop to the exp of the voltage. So this lead para needs rewording. Any suggestions?--Light current 01:09, 5 October 2005 (UTC)

I rewrote that sentence. Snafflekid 05:28, 5 October 2005 (UTC)

The basic problem, which is currently not emphasised, is that BJTs and FETs operate in different ways. You push some current into the base of a BJT and more current flows thru the E/C terminals. On the other hand you put a voltage between the source and gate of a FET and it conducts a proportional current between the source and drain. In both cases this current flows regardless of the e/c or s/d voltage (provided that the e/c or s/d voltages are above saturation). Simple as that. CPES 02:05, 24 April 2006 (UTC) (80.177.169.33)

Not exactly. BJT transconductance (ratio of C-E current to B-E voltage) is exponential, whereas FET transconductance is parabolic. Neither one is really proporional in input voltage. Sure, BJT collector current is more or less proportional to base current (beta), but it's highly variable based on temperature, current, and even individual device. BJT circuits are usually not designed based on a specific value of beta, you can't depend on it. One a specific die, two devices will have the same beta, but it's hard to control. Conversely BJT circuits are designed based on transconductance, which you can depend on. FETs are a real problem, their transconductance can vary by a factor of two or more for a given device. Take a look at the specs for the venerable MPF102. IDss and Vgs(off) vary widely. As for pushing a current into G-S of an FET, you can use your imagination ;-) Madhu 22:36, 25 April 2006 (UTC)

Transistor biasing-The most basic question

Why is the base-emitter junction of the transistor forword biased and the collector-base junction reverse biased?Why not the other way round?

If the BJT is used in the forward active mode (which is almost always the case) the collector voltage is higher than the base voltage and the base voltage is higher than the emitter voltage. For an N-P-N you get the condition you mentioned. If the collector is pulled low enough it will become forward biased also, this is called saturation. Snafflekid 17:22, 8 December 2005 (UTC)

If you biased the B-E and C-B junctions as mentioned by the original (anonymous) poster, the collector and emitter terminals would be reversed (more or less). This does work, but not very well. In normal configuration, if the B-E junction is not forward biased, no current will flow into the base and no transistor action will result. Transistor action is not necessarily intuitive, that's part of the reason why BJT discovery was more experimental than theoretical. FETs are more intuitive, but fabrication was harder in the early days. Madhu 23:46, 8 December 2005 (UTC)

Well, in an npn BJT, the emitter is usually heavily doped n-type compared to the collector. This is to optimize the forward-active operation of the BJT. So, for a non-optimized BJT (which are rare), your question would be valid. —Preceding unsigned comment added by 69.225.195.234 (talk) 03:29, 17 January 2008 (UTC)

Woops. Can't believe I missed this, but I meant "this is to optimize the backward-active operation of the BJT." —Preceding unsigned comment added by 69.225.195.234 (talk) 00:47, 24 July 2009 (UTC)

Needs Simpler Explanations

Not everyone who comes to this article is as technically informed as the authors. It's important that this and other technical and scientific articles include basic information and explanations for the less informed. After all, that's what they're here for---to get informed. Tmangray 08:10, 23 December 2006 (UTC)

Exactly what is unclear? Is the lead paragraph OK? If not, try to fix it. If something later is unclear, then please point it out or try to fix it. The complexity is bound to increase beyond what nontechnical readers can handle at some point, but if you point out at what point it needs simplification, perhaps it can be improved. And of course we will all agree, I think, that it is inevitable than in an article on a technical topic "Not everyone who comes to this article is as technically informed as the authors." That doesn't mean we're not sympathetic to the problem. Dicklyon 08:46, 23 December 2006 (UTC)

The intro looks fine to me. — Omegatron 06:19, 25 December 2006 (UTC)

I thought so, too. But then I looked again, with an eye to whether you and I are more part of the problem than of the solution. Perhaps so. So I attempted a simplification, at least by moving a few of the less "simple" concepts to a second paragraph. See what you think; hopefully I didn't lose anything. Dicklyon 07:05, 25 December 2006 (UTC)

The OP's concern is a lot easier to voice than to solve. I've tried for a while to think of a one-liner that simply and adequately explains what a transistor is and/or does. I don't really think there is such a thing. Transistors can be simple devices, but the principles that govern their operation are not readily accessible to the lay man (high school level electromagnetics are a minimum requirement, basic quantum mechanics and solid-state physics are preferable). Complicating things further is the fact that devices which work in very different ways (say, a BJT and a FET) are all lumped into the category of "transistor". The lead of this article as it currently stands is decent, but I'm not too sure if I like the whole "small signal controlling larger signal" general assertion. I think that this is usually true from an application point of view, but I can think of counterexamples (e.g. follower stages in amplifiers). It's on the right track, but I think it could be improved some. I'll look back through some of my semiconductor physics textbooks to see if they offer any decent terse "definition" of a transistor (I'm doubtful). -- mattb @ 2006-12-25T22:12Z

No such luck... All of my texts avoid actually defining a transistor and just start talking about how they work. I looked at a copy of Britannica, and it adopts a purely functional definition of the transistor. Rather than attempting to explain at the outset "what transistors do", it starts with "what they are used for". I think this might be a very good approach. Pursuant to this methodology, I think an adaptation of the first sentence in the second paragraph might be good. Let's try to think of the most general categories of application transistors can be used for... Off the top of my head, I'm coming up with signal amplification and control (switching, voltage regulating). I'm a little hesitant about including oscillators so explicitly, since an oscillator is much more a certain circuit topology than a device. I realize that this is somewhat an artificial distinction that could just as well be applied to any use of a transistor, but I think it's much easier to make the argument that a transistor can, on its own, behave as an amplifier or a switch than an oscillator. Anyway, let me know what you think. -- mattb @ 2006-12-25T22:34Z

I think the concept of a small signal controlling a larger one is fundamental, and it certainly does apply to a follower, which is a current amplifier. Plenty of good simple definitions are available to draw on if we need more inspiration: [1]. Dicklyon 02:06, 26 December 2006 (UTC)

It's a controlled valve. — Omegatron 07:43, 26 December 2006 (UTC)

It's a solid-state alternative to a controlled valve (using the British meaning of valve). Dicklyon 16:16, 26 December 2006 (UTC)

You could go that route, but I don't think it's a particularly useful comparison for introductory purposes. Someone who doesn't have a good grasp of transistors will not likely understand valves (tubes) well enough to benefit from the one-liner. If we're talking about the hydraulic analogy of circuits, yick... Let's not go there, please. I'm still not entirely sold on the "small signal controlling larger signal" statement. I certainly see the logic behind saying that, but I'm not convinced that it's the best way of summarizing transistor operation. I don't think it neatly covers the switching role of transistors, and I still think it's awkward to apply it to unity or sub-unity amp stages. I feel that a terse statement to the effect that "transistors are semiconductor devices used for electrical signal amplification and control" would be a nice way to cover all the bases. If you folks really want to stick with the small signal/large signal explanation, however, I guess that's okay too. -- mattb @ 2006-12-27T21:12Z

The opening is still vague and obtuse. Given that transistors replaced vacuum tubes, is it fair to say that they perform the same function? If so, perhaps you can use some of the narrative from the vacuum tube description, which is clearer to me: "In electronics, a vacuum tube, electron tube (inside North America), thermionic valve, or just valve (elsewhere, especially in Britain), is a device used to amplify, switch, otherwise modify, or create an electrical signal by controlling the movement of electrons..." 144.226.230.36 (talk) 21:34, 14 February 2008 (UTC)

Clear lay presentation

This article seems poorly organized. Above all, there is no early, clear description of the basic mechanism by which, for example, NPN and PNP transistors work, suitable for a lay person. This is not complicated to sketch out (one could just choose one of the types for simplicity's sake) and would make the article much more accessible. Hgilbert (talk) 12:39, 11 March 2008 (UTC)

Physical layout of a transistor on IC

Please note also that all of bipolar PNP and NPN and JFET do not have graphics or scheme displaying physical layout of the transistor. I can try to do something according to that what is in my University textbook, but I will not do it w/o consulting others.

A simple, basic layout, even 3D, cannot hurt the matter anyway. -- Mtodorov 69 13:42, 10 March 2006 (UTC)

Images & Symbols

Does anyone have a copyright free picture(s) of transistors we could use at the top of the page to replace the rather grey looking one.?--Light current 17:25, 9 November 2005 (UTC)

Here are some more: commons:Category:Transistors — Omegatron 18:02, 9 November 2005 (UTC)

Replace lead pic with better one. This is still not a very good pic and we need a better one if we are to submit article as a featured article.--Light current 18:28, 9 November 2005 (UTC)

I added one I just took. --agr 20:43, 11 November 2005 (UTC)

Thanks. Thats better!--Light current 20:58, 11 November 2005 (UTC)

A picture of the 'chip' inside the transistor would be nice too.

I just did a Google Search. There r bout 67,000 images. But not sure how many r copy right free. I found this [2] much better. Most of the images can be used on wikipedia. --Electron Kid 02:34, 29 January 2006 (UTC)

Can we get some close-up pictures, like on [3]? We could ask manufacturers, as they did. — Omegatron 22:25, 8 November 2006 (UTC)

I guess we could, though I have my doubts about the utility of such things... Most optical photographs of functional transistors (including the ones you linked, I think) are just going to show the top metal layers or contacts. SEM photographs might be slightly more interesting. -- mattb @ 2006-11-09T00:07Z

P.S. - I can take plenty of optical microphotos of various forms of transistors... Getting an SEM image might be more difficult, though. -- mattb @ 2006-11-09T00:10Z

Most optical photographs of functional transistors (including the ones you linked, I think) are just going to show the top metal layers or contacts.

So what? Most people can never see even that. — Omegatron 16:45, 8 December 2006 (UTC)

Pictures

Currently there are two images of thru hole trans, both essentially showing the same thing. The original image (with tape measure) is best, because it shows a progressive size range and indicates scale. Suggest image presently in intro be removed and "tape measure" tran image be moved to intro. An image of surface mount trans would compliment the thru hole image: there once was one but it seems to have got lost in the major revision of tran page. (nice to see the better tran symbols image has been reinstated: but still no IGFET symbols in it) - CPES 20:21, 26 April 2006 (UTC) (80.177.169.33)

Any chance someone could check norm to put correct symbils into page. Quick check of other language versions showed pretty much every use different symbols.

Types

This section is becoming more a laundry list than an informative and useful bit of prose. I don't see much utility in enumerating every major variation of transistor. I think it ought to be trimmed way down and just cover the three basic classes; FET, bipolar, and experimental. -- mattb @ 2006-10-20T03:06Z

Good point. KIS is always best. CPES 23:28, 25 October 2006 (UTC)

I think that a distinction needs to be made here between distinctly different operating types (as in bipolar, FET, UJT, etc.) and differences in manufacturing processes, which have had very little relevance to me as a _user_ of the parts over the years. At least split the list of types into two areas maybe? --Rtellason (talk) 06:56, 2 January 2008 (UTC)

Photo transistors

Now that the weird "photo fet" has been pointed out, we really need a section on photo-transistors to explain a bit about how these things work, and why the "photo fet" is a sort of bastard stepchild of a photo-transistor (OK, maybe not in those terms). Here's one explanation. Saying the light makes the FET conduct is bit too misleading, in my opinion. Dicklyon 15:58, 30 October 2006 (UTC)

Here's another that explains the photo-fet as a combination photo-diode and fet. Dicklyon 16:00, 30 October 2006 (UTC)

Gracious that second book looks pretty old... The wording makes it seem like it was written before the interaction of photons with semiconductors was well understood. Anyway, as I've seen the term used, "phototransistor" can include a lot of fairly different devices. The only real constant is that there's some sort of quantum interaction between photons and EHPs going on in a semiconductor. Beyond that you could be using a heterojunction system, a MOS system, a traditional bipolar system, etc. That's the reason I objected to the phrasing of the added text; it suggested to me that phototransistors all use photon-related RG current in exactly the same way, which isn't true. -- mattb @ 2006-10-30T16:16Z

Yeah, 1989; ancient history; oops, no, I made a light-sensing NMOS chip in 1980; Chamberlain did in 1968; of course, the photosensitive parts were the isolation diodes, not the transistors. My point is that in the photo-fet, the light doesn't make the transistor conduct, or not in a way analogous to the inherent transistor action on photocurrent that you get in a BJT. A few words to explain the two, and their difference, could be useful. Dicklyon 16:22, 30 October 2006 (UTC)

Reason for reversion

The following two paras were reverted out of the tran page with the edit comment below:

Photo BJT

"Bipolar transistors can be made to conduct by light (photons) as well as current. Devices designed for this purpose have a transparent window in the package and are called phototransistors."

Photo FET

"Like bipolar transistors, FETs can be made to conduct by light (photons) as well as voltage. Devices designed for this purpose have a transparent window in the package and are called phototransistors."

Edit Comment

"phototransistors don't "conduct" photons (or voltage, for that matter); the photons cause RG current... Plus the effect isn't limited to bipolar transistors"

I can't understand the edit comment (putting aside the photo FET issue for the moment). Neither paragraph states that phototransistors "conduct" photons or voltage and neither paragraph says that the effect is limited to bipolar transistors... or am I missing something? CPES 02:56, 31 October 2006 (UTC)

I didn't notice the "by" in there when I reverted. My bad. Anyway, see Dick's comments one section above. -- mattb @ 2006-10-31T03:04Z

Oh, I see. Its been driving me mad trying to figure it out. Thanks CPES 03:13, 31 October 2006 (UTC)

Revised wording: photo BJT and photo FET

Well put (I think it is important to cover opto aspects) CPES 10:42, 1 November 2006 (UTC)

I've never heard "Photo BJT". Let's don't use it without a good source. Dicklyon 21:43, 1 November 2006 (UTC)

Photo BJT in this case is just used to differentiate between photo aspects of BJT and photo aspects of FET(photo transistor could be interpreted to cover both BJT and FET). I meant that it is important to cover the opto aspects on the tran page for both BJTs and FETs, rather than say nothing, and that the revised wording is all that is needed. I was not suggesting that any new information on opto be added to the tran page. CPES 08:50, 2 November 2006 (UTC)

Opto FETs

I seem to remember that optically activated FETs are available. If so, this should be mentioned in the appropriate paragraph.--Light current 02:06, 4 October 2005 (UTC)

I don't know if discreet opto-FETs are available, but they're certainly available when packaged with an LED as an optical isolator.

Atlant 12:44, 4 October 2005 (UTC)

Yes thats what I meant. Thanks for confirming--Light current 23:31, 4 October 2005 (UTC)

Discrete photo fet at: http://www.linearsystems.com/datasheets/LS627.pdf I think there are a load for hs fibre rx too. But most are in optocouplers as said. Here is some description stuff: http://www.radio-electronics.com/info/data/semicond/phototransistor/photo_transistor.php - CPES 23:36, 27 April 2006 (UTC)

SETs

Single-electron transistors are not mentioned at all in the article and neither have a page of their own. Could someone fix this? --Khokkanen 20:57, 22 March 2006 (UTC)

I added a mention to this article. We have an article on the SET. --Heron 22:05, 22 March 2006 (UTC)

Single molecule transistors

See http://www.photonics.com/content/news/2006/September/1/84283.aspx

Multiple emitter

Perhaps a section should be added on multiple emitter transistors, an important topic in electronics.

Ordinary Person 22:24, 1 October 2006 (UTC)

Stuff here and there and re-arrangement needed

Two types of transistors? I believe we do have a gazillion types of transistors these days. Perhaps we should accurately say, "in the beginning, there are two basic types of transistors, BJT and FET".

Looks like this article need some re-arranging. The types were described above (Semiconductor type, power ratings, etc), and then towards the bottom, we see BJT, FET, etc. They can probably live happily in one section. I am translating this page into wiki:id, I'm lucky as no one will protest the way I'm arranging the sections, heheheh... Kortsleting 03:23, 18 August 2005 (UTC)

No makers list please

Matt, good job deleting the spam-magnet list of makers. I was tempted, but not as bold. Dicklyon 05:03, 30 November 2006 (UTC)

Thanks for the word of support... I had the evil idea of adding my own lab to the list if someone re-added it. (just kidding) -- mattb @ 2006-11-30T05:42Z

Math/TeX changes

I changed a couple equations regarding the collector/emitter and gain/drain/source proportions. First, for example, "I_ce" seems more appropriate than "Ice". Secondly, the proportional equation is a bit easier to write in TeX (and looks better ;p), so, yeah. -Matt 16:30, 28 June 2007 (UTC)

Testing

please add how to determine whether an unknown transistor is a PNP or NPN type with just the aid of an Ohmmeter. —Preceding unsigned comment added by 210.213.87.23 (talk) 04:27, 18 September 2007 (UTC)

You have to first know which lead of your ohmmeter is positive, and you have to know that your ohmmeter has a decent open-circuit voltage, such as applied by a 1.5-volt cell. If you have an NPN, you'll get a low resistance reading from base to collector or emitter when you put the positive lead on the base, and high resistance the other way around. Reverse for a PNP. But that only belongs in the article if you find a reliable source for it. So pick one. Dicklyon 05:11, 18 September 2007 (UTC)

Page size

The page is getting big. I suggest we put the more technical BJT and FET stuff (equations, models) on the respective device pages. - mako 07:32, 30 December 2005 (UTC)

I had the same thought. This page gets bloated regularly. Snafflekid 15:44, 1 January 2006 (UTC)

I moved the BJT stuff off to the BJT page. I'm not familiar with the equation in the FET section, though; where does it belong? - mako 05:35, 22 January 2006 (UTC)

"There is no need for haste." See Wikipedia:Article size. — Omegatron 01:50, 14 October 2005 (UTC)

32kB is just a suggestion. However, transistor has a very big field to cover. Snafflekid 02:04, 14 October 2005 (UTC)

This page is minuscule compared to the actual complexity in the art of transistor making and integration.

A huge subject to the point that A page with 32K as sugested would have no text at all but an intro and sub section to other pages.--Transisto (talk) 01:28, 13 February 2008 (UTC)

Cost in $

Subject deemed of little importance, moved to talk:transistor/Archive 2#Cost in $

Transisto (talk) 07:24, 16 February 2008 (UTC)

ChrisnHouston's edits

Chris, I have problems with a bunch of your recent edits. The new lead paragraph introduces an unsourced analogy, unnecessarily introduces FET-only terminology, confusingly uses the word valve which has another meaning in electronics, and proposes a modified theory of transistor naming. Your linearity comments are way off base, since linearity is a property of a circuit, not of a transistor. The harmonic distortion statement is unsourced. You may have some good ideas here, so try again, more carefullly, with sources; for now, reverting all. Dicklyon (talk) 04:58, 28 December 2007 (UTC)

That analogy was added as a simplified way to understand the device. Analogies are never perfect, or they wouldn't be analogies. The source/drain/valve terminology refers to the faucet. And vacuum tubes, transistors and faucets all share a common function of acting as valves. Water was engineered long before electrons were, and much of the terminology was adopted through such analogies. My effort was toward making the article far more easy to understand for anyone wanting to learn about the transistor. You see potential in those efforts and instead of building upon it, your chosen course of action is to tear it down. Curious. And I'm sure you're well aware that amplification and switching are properties of circuits too (and not transistors in themselves alone). If you were consistent in your approach to Wikipedia here, you would have deleted a lot more than just my contributions, especially seeing how there are only five references on the entire page presenting many dozens of statements. An alternative Wikipedia strategy is one of incremental building, where if some bricks are seen to be crooked, you can tweak them straight and keep on constructing instead of knocking a whole wall down. ...something you might want to consider next time you feel the desire to use anti-vandalism tools in response to contributers you see to have constructive intent. ChrisnHouston (talk) 10:55, 29 December 2007 (UTC)

Nand chip transistor count

There was no mention of transistors on the referenced site. It was used as a reference for this sentence: "For example a microSDHC flash memory the size of a fingernail can contain more than 50 billion transistors."

Smithg86 (talk) 00:39, 10 March 2008 (UTC)

not a good references but... more on the subject

this chip has 2 bit per cell (MLC) or 12*8/2 = 48bln T (minimum)

(fun fact) boasts a whopping 50 billion transistors. Harari mused that if you took that many ants and sat them in a line, they’d circle the earth twice! [4] and newer 32GB [5]

Ps: edited flash memory capacity with Sandisk pressroom links --Transisto (talk) 12:23, 4 April 2008 (UTC)

Paper transistor

This statement was just added by a user with just an IP address: "As of July of 2008, a Portuguese research team of Universidade Nova de Lisboa has successfully created the first paper transistor, which is expected to revolutionize the high expenses connected to that industry". There is a citation to the BBC in the Portuguese language. I don't understand Portuguese, but it seems to say something about a publication in Electron Device Letters. Can someone who speaks Portuguese (or who reads every issue of Electron Device Letters) provide a citation to that publication, or figure out some information that would help in searching, such as the issue, author name or article title? --Gerry Ashton (talk) 18:37, 26 July 2008 (UTC)

Accurate but certainly too new to be in history section... High Performance Flexible Hybrid Field Effect Transistors based on Cellulose Fiber-Paper will be published next September in IEEE Electron Device Letters. A page should be made for it and then added to "transistor types" section.--Transisto (talk) 05:17, 30 July 2008 (UTC)

I am Portuguese, and I think I can help. What sort of help do you need with the article? Samuel Lourenço (talk) 15:56, 7 November 2009 (UTC)

I think that the article in IEEE Electron Device Letters should have been published by now, so someone with access to that publication could write an appropriate article. That publication is in English. --Jc3s5h (talk) 15:59, 7 November 2009 (UTC)

You can see the abstract at IEEE Explore (or the whole thing if you have a subscription). And what on earth is ldquointerstraterdquo structure and why don't we have an article on it? SpinningSpark 22:13, 7 November 2009 (UTC)

Article too difficult: hint

Today I studied the concept of a transistor, which was totally new for me. Although this article contains useful information, it did not really help me to understand the concept. Luckily, I found a very understandable, useful and probably very reliable tutorial at nobelprize.org: [6]. I advice to use the explanation strategy of that tutorial in this article, in an extra paragraph after the introduction. Kind regards, Templatehater (talk) 22:23, 11 December 2008 (UTC)

Greatest invention?

I don't understand what people don't like about reporting that many consider the transistor to be the greatest invention of the twentieth century. This is a sourced fact (the fact that many consider it, which leaves room of course for many to have other opinions as well). There can be no doubt that it's true; probably each of us knows many people who if pressed to think about it would consider it to be the greatest, but that's not really the point; the point is that a book, a reliable source, reports it. Dicklyon (talk) 09:23, 31 December 2008 (UTC)

No problem if its kept, but it just looks like peacock, even if sourced. "...promote the subject of the article without imparting real information." Yes, some author says that transistor is the greatest invention, but the importance of transistor can be summed up by stating actual facts of how transistors are used extensively in almost all electronic gadgets rather than quoting somebody. --Unpopular Opinion (talk) 16:15, 9 January 2009 (UTC)

It's not a peacock term, it's a well sourced indication of the esteem in which this invention is held compared to others of the 20th century, such as the airplane, computer, etc. There are plenty of other good facts there to back it up, but you can add more if you like. Dicklyon (talk) 03:01, 10 January 2009 (UTC)

Hi Dicklyon, rather than making the claim that this is the greatest invention etc, a better approach might be to let the facts of the transistor speak for themselves. This looks to be exactly what WP:peacock advises against. I know it's referenced, but the reference you've used to back this claim up is pretty weak. It's a one liner (almost repeated verbatim in the article), itself without any corroboration, stated as a lead-in to a section on microprocessors in a management text. It doesn't report it in any sense; it states it for dramatic purpose. Lissajous (talk) 07:39, 16 October 2009 (UTC)

Hi all... I'll just add that citing anything as the "greatest" of its kind is a far too vague and subjective claim and of no real value, and therefore it serves no substantive purpose to note within an article that "many consider" something as the "greatest" anything -- greatest hit, greatest band, greatest show on earth.

More appropriate perhaps would be to note that many historians of technology consider the transistor the most significant (or whatever the adjective) development in electrical technology in the twentieth century, if that's indeed the case and the assertion can be properly sourced; "greatest" simply has no meaning. Personally, I dislike applying superlatives to things; "among the most significant" (there's gotta be a better word) should suffice. Cheers, Rico402 (talk) 13:17, 16 October 2009 (UTC)

"The social consequences of the application of the transistor invention are, of course, what is really of most significance." - William Shockley

• William Shockley, "The invention of the transistor - an example of creative-failure methodology", p.26, Semiconductor Silicon, 1998: Proceedings (Electrochemical Society), 98-1, ISBN 1566771935, reprint of original from The Public Need and the Role of the Inventor, Washington, DC: Government Printing Office, 1974.

"The invention of the transistor and everything that grew out of that has spawned a second industrial revolution that is at least as important as the first industrial revolution" - Miles Klein

• Lillian Hoddeson, Vicki Daitch, True genius: the life and science of John Bardeen : the only winner of two Nobel Prizes in physics, p.306, Joseph Henry Press, 2002 ISBN 0309084083, quoting Miles Klein

"And it was the beginning of a technological revolution of far greater consequences than anyone could have envisioned at the time" - Ralph Bray

• Ralph Bray, "The invention of the point contact-transistor: a case study in serendipity", ULSI science and technology/1997: proceedings of the Sixth International Symposium on UltraLarge Scale Integration Science and Technology, p.37, The Electrochemical Society, 1997 ISBN 1566771307.

"One of the most revolutionary inventions of the twentieth century, the transistor, was effected at Bell Labs in December 1947."

• Mauro Dardo, Nobel laureates and twentieth-century physics, p.255, Cambridge University Press, 2004 ISBN 0521540089.

SpinningSpark 15:59, 16 October 2009 (UTC)

Certainly I agree that we have no business making claims about something being the greatest; but reporting an expressed opinion, or a summary of expressed opinions, from a reliable source is a whole different matter. And I did tone it down to what the source reports, namely "The transistor is considered by many to be one of the greatest inventions of the twentieth century." This is true, and it's sourced; of course many also have other opinions about's the greatest invention, and this doesn't interfere with that. I think the way to go here would be report more from the sources that SpinningSpark has just shown. Dicklyon (talk) 16:26, 16 October 2009 (UTC)

I agree for the most part, and cheers to SpinningSpark for the above quotes, but a few may be a bit over the top; in other words, I don't think it's constructive to quote hyperbole. I certainly can't argue with "One of the most revolutionary inventions of the twentieth century", but I'm not convinced that the transistor in and of itself "spawned a second industrial revolution that is at least as important as the first industrial revolution". I would argue that it was electrical/electronic technology that "spawned a second industrial revolution". But I'm sure you guys will work it out. Cheers, Rico402 (talk) 17:32, 16 October 2009 (UTC)

Well, personally, I agree with this hyperbole, so maybe I'm biased, but it seems to me that it's a good idea to report attributed opinions here, whether we agree with them or not. If there are sources where people have tried to specifically address the question in a balanced way of what is the most important invention of the twentieth century, or just what was the impact of the transistor, those should be reported most prominently. And some others that conclude the Haber–Bosch process or the Computer or the Integrated circuit or the Microprocessor or the Birth-control pill or the Remote control or perhaps other things were most important. Dicklyon (talk) 17:51, 16 October 2009 (UTC)

The only quarrel I have with with "considered by many to be one of the greatest inventions" is the word "greatest"; is this not a "weasel word"?. There's simply no objective criteria for determining what is "greatest". Shouldn't such words be avoided even when quoting a reliable source? It seems to me that quoting a claim that something is "the greatest" requires further explanation, i.e., why does so-and-so make the claim "greatest". If that were included I suppose I wouldn't have a problem with it. But for what it's worth, "One of the most revolutionary inventions" avoids these problems. The assertion is self-explanatory, objectively true, well-sourced, and nonexclusive (i.e., it doesn't claim the transistor is THE most revolutionary invention). Cheers for the good work! Rico402 (talk) 07:38, 17 October 2009 (UTC)

PS: Re "sources where people have tried to specifically address the question in a balanced way of what is the most important invention ... those should be reported". Given authoritative sources, I totally agree. Re whether such statements should appear "most prominently", I'm assuming you mean in contrast to less authoritative or more subjective claims. If that's the case, again we are in full agreement. As usual you make a very cogent argument. Nicely done. Cheers, Rico402 (talk) 08:24, 17 October 2009 (UTC)

We're not saying it's "greatest", just acknowledging that many have expressed that opinion; how are we supposed to guess what criteria they were using? Dicklyon (talk) 07:46, 17 October 2009 (UTC)

We shouldn't have to guess. The quoted source should cite what criteria were used to arrive at such a conclusion -- industrial or employee productivity, economic impact, social impact, etc. -- otherwise there's no context and "greatest" is a meaningless term. If the source doesn't specify some basis for such a claim, then it's unsupported, impossible to verify, and thus has no business in the article. Sorry to sound so pedantic, but all I'm really asking for is to know what is meant by "greatest"; all the rest is of little consequence. Cheers, Rico402 (talk) 08:44, 17 October 2009 (UTC)

That's not the way it is. The quoted source says "many consider it to be..."; why would you expect that author to have surveyed the many to try to understand why? Dicklyon (talk) 16:29, 17 October 2009 (UTC)

Why would anyone expect otherwise??!! The whole essence of such a claim is in the "why". (Why "greatest"? The reader deserves to know.) You're quoting a secondary source making a vague claim totally devoid of context. It just doesn't wash. This is a technical article, not some pop culture blog. It should bear up under scrutiny by historians of science and technology. I've authored plenty of technical reports and advised numerous clients on technical matters (specifically geotechnical). If I couldn't have given the "why" I would have been tossed out on my ear. Why even bother quoting someone who can do no better than offer the meaningless statement "many consider ... the greatest". Rico402 (talk) 08:57, 18 October 2009 (UTC)

PS: I've said my peace (and then some), but I'm through; many apologies if I sounded harsh. My hope is that you'll go with one of the other quotes that Spinningspark has offered, but I won't edit war (or make any further fuss). You've made many valuable contributions to articles we've both worked on, and for that and your engaging and polite demeanor on the Talk pages I'm grateful. My respect for you remains undiminished. Cheers!, Rico402 (talk) 09:27, 18 October 2009 (UTC)

Thanks for your input. I agree it could be made better with one of SS's source, and I expect he'll work on that. My point was only that the present statement is not bad, and is well supported by sources, including the one cited; it simply summarizes a bunch of sentiment about the importance, and talks about how it was "desparately needed" and led to a lot of modern wonders (small computers and all that they enable); this isn't the same as saying why all those many people considered it greatest, but it's something. Sorry for being so argumentative; probably some spillover from other ongoing junk. Dicklyon (talk) 15:25, 18 October 2009 (UTC)

I pretty much agree - the source could be better but it is a widely held view and is worthy of inclusion. There is often a tendency in articles on technical subjects to suppose that the entire article should be technical in nature. I don't agree with this: while it is important to keep a tight focus on the nominal subject, putting the subject into a wider context is also important. Few would doubt that the transistor has changed the modern world and illustrating its impact on modern society is just as important as a description of the theory of operation or when and where each form was invented. CrispMuncher (talk) 18:47, 20 October 2009 (UTC)

Bell Labs

Whyfor is there no mention of Bell Labs, where the transistor was originally developed? Forshame!  :) //Blaxthos ( t / c ) 15:23, 15 February 2009 (UTC)

Shame? Hardly. I just added it, as you could have done. Dicklyon (talk) 20:23, 15 February 2009 (UTC)

suggest using a infobox

Streamlining electronics articles I suggest using the infobox below (I could not find a better symbol drawing)--Thorseth (talk) 09:35, 23 February 2009 (UTC)

Transistor

Assorted discrete transistors.
Type	Active
Inventor	Julius Edgar Lilienfeld (1925)
Pin names	Base (B), Collector (C) and Emitter (E)
Electronic symbol
BJT type

I can only think of two articles that could use the infobox, this one and Bipolar Junction Transistor. Don't forget that MOSFETs and JFETs are transistors too. --Gerry Ashton (talk) 15:30, 23 February 2009 (UTC)

Getting the curves right should be more important than infobox page decorations. --Wtshymanski (talk) 16:12, 23 February 2009 (UTC)

Plus that infobox is full of weird non-informative stuff, like bad symbols, words like "pin configuration", parenthesized letters with no apparent reference to anything, attribution of inventorship to one relatively obscure inventor who as far as we know didn't make one work (and the thing he invented was a FET, not a BJT as shown here). Bit of a mess. Dicklyon (talk) 06:32, 24 February 2009 (UTC)

Well, first of all you can look at Resistor, Capacitor, Inductor and LED to see other uses of this infobox. I have no input to the curves issue, but I could put some effort into finishing this box. Furthermore if the guy that patented the first transistor can't be attributed as the inventor, I don't know who can. As I wrote, this was the best drawing I could find, it is now changed. I know there are many types of transistors, but I suggest showing the one most commonly used, if it is not the BJT NPN then some other good example.--Thorseth (talk) 09:50, 24 February 2009 (UTC)

Please do not use the title "Transistor" and then show only one of the multitude of transistor symbols. That is like having a box titled "passive component" and putting a capacitor symbol in it. --Gerry Ashton (talk) 17:53, 24 February 2009 (UTC)

Agreed. I don't think such an infobox can possibly do justice to the concept of "transistor". Trivializing the inventorship issue by listing one guy, as opposed to the guys who got the Nobel prize for making it work really, and showing one type that's nowhere near the most common type (which is the n-channel MOSFET) nor the type that the listed guy invented, etc., doesn't lead to anything useful or informative. There's no need to try to make the transistor topic as simple as resistor or capacitor. Dicklyon (talk) 03:01, 25 February 2009 (UTC)

The article already has a image of a "generic" transistor:

Why not use this as the symbol then? Or if the MOSFET type is the most used type then why not depict that? If it's a big problem to credit the inventor (patent) as the inventor ... then I guess a "First build by:" could be added to the fields in the box. I think an infobox is a great way to get a quick overview of a subject, but I am not going to push for it if you oppose the idea as strongly as you seem to do.--Thorseth (talk) 09:38, 25 February 2009 (UTC)

When I made the infobox template, I intended it to be used for specific devices, while the transistor is really a family of different devices. I think it's reasonable to use the template for specific types of transistor, but it would be difficult to use for this article. Papa November (talk) 23:10, 1 March 2009 (UTC)

wiring two diodes together

I tried to re-express the statement about you can't make a transistor by wiring two diodes together. It's more clear, I think, to give some minimal conditions under which putting two pn junctions together will make a transistor, and that condition is that they share a semiconductor base region. On a chip, you can indeed put a pair of lateral pn junctions next to each other, "wired" via a diffusion, and get a transistor, though this is not the typical way to get a good one. Dicklyon (talk) 15:49, 20 June 2009 (UTC)

But you cant go into a store and buy 2 diodes and wire them together to make a transistor (this is what 'simply' wiring together 2 diodes would mean to most people). that should be made clear. just-emery (talk) 17:21, 20 June 2009 (UTC)

Both of your versions look good, and both make perfect sense. For Wiki purposes, I would lean towards just-emery's version, as anyone who understands what "sharing an intervening semiconducting region" means probably already knows that connecting two diodes together does not make a transistor. "Simply wiring two junction diodes together will not make a transistor" would probably be most easily understood and informative for someone who is just starting to learn electronics. Retraction. I went back and re-read the section. It's technical enough that Dicklyon's version fits in just fine. It doesn't need to be simpler, IMHO. Wildbear (talk) 18:27, 20 June 2009 (UTC)

Yes, now that I think about it, I see the error of my ways. it is much better that way. Wikipedia is lucky to have editors like Dicklyon improving its articles. just-emery (talk) 22:19, 20 June 2009 (UTC)

Prefixes for transistor types

Prefixes are definitely wrong, sorry: http://de.wikipedia.org/wiki/Halbleiter-Kennbuchstaben —Preceding unsigned comment added by Hollunder (talk • contribs) 09:40, 20 July 2009 (UTC)

Different systems of prefixes are used in different countries. --Jc3s5h (talk) 12:19, 20 July 2009 (UTC)

Internal Construction

Does anyone here know how a typical upright half-circle surface mount transistor is made? how? Most results in trying to understand what the inside of a transistor is like results in a simple diagram of 3 blocks, labeled N P N with wires attached to them. There's a difference between the collector and emitter layers, but it's never illustrated clearly. I took a transistor apart once, and found a metal plate with a tiny square of silicon embedded on it, with two metal tabs that, to my knowledge, had cat whiskers attached to the back side of the chip, But I couldn't see them as I was unable to remove the epoxy on the other side of the heat sink. —Preceding unsigned comment added by 24.156.21.27 (talk) 21:34, 5 July 2009 (UTC)

• Here's a rough diagram of the interior, but the actual design of the chip is still unknown. http://img21.imageshack.us/img21/4061/transistor.png —Preceding unsigned comment added by 24.156.21.27 (talk) 21:50, 5 July 2009 (UTC)

They're made by a process called photolithographic epitaxy (using photoresist) (try googling or google imaging for photolithography or "epitaxial transistor" and you will find pictures like this [7] and [8]). The reason that process is used is because you can make a whole bunch at one time, i.e. mass produce, and that makes them inexpensive.

The process is similar to making a (chemical) photograph, where there is a chemical reaction caused by light, which you control by projecting the light in a pattern. Imagine that you pour a special liquid plastic (called photoresist) onto a surface, and then expose it to light in a pattern, where the light will make the plastic get hard. Now you rinse away the liquid plastic, and you have left a hard plastic pattern that matches the pattern of the light (i.e. a picture of your face if you projected a pattern of light that looked like your face). Now pour acid on the surface, and the acid will etch the surface where there is no plastic; where there is hard plastic, the surface will be protected. Alternatively, instead of acid, you could "rain" or "snow" down a layer of something different, which would not stick to the surface where the plastic was. Alternatively, you could bombard the surface with chemicals that would cause a change to the substance of your surface (e.g. by adding + or - impurities to a crystal of a semiconductor), with other parts protected by the plastic. Now, scrape/dissolve away the hard plastic and you have constructed a complex pattern on your surface. You can now repeat these steps with a different pattern on top of the previous one, and build up several layers. Instead of your face, use pictures of transistors and voila, you have transistors. BTW wikipedia, you need more simple explanations like this instead of the complicated complicated pages that only experts can understand 71.190.66.244 (talk) 20:29, 24 April 2010 (UTC)

Confusing

I have found this article very unorganized and confusing. While explaining that Transistors are electronic switches, and that are several types, in addition to the fact that they assemble into logic gates, etc., nowhere is there a simple encyclopedic description of what a transistor actually is in terms of physical functionality.

There are claims that it underlies the basis of modern electronics, but no elaboration as to how. As such I find the article overall very unhelpful from a novice/informational standpoint. Commissar Mo (talk) 10:30, 5 August 2008 (UTC)

There are two commonly used types of transistors (bipolar junction non-FET (BJT) versus MOS FET), and they work completely differently, so one description will not explain both. It is not possible to completely understand how transistors work without quantum mechanics, but here is a "handwaving newtonian" explanation that will move you closer for a BJT. You need to already understand what electrons are, and what an electric field is: if you put a free electron into an electric field, the force of the field on the electron will make the electron move, the electron will accelerate, and the stronger the field, the more acceleration, after which the electron could be said to have absorbed power or energy. A BJT transistor has an electric field in it, formed and increased when you reverse-bias (e.g. hook up a battery to) a PN junction (reverse bias makes the depletion zone wider, no electrons keep flowing, but you get a nice electric field sitting there). It is a real electric field, one that if we put a free electron in it, will cause the electron to accelerate. Now consider a microphone: a microphone takes the pattern of energy in the vibrations of air (e.g. from your voice) and converts it to a pattern of electrons with energy that corresponds to the vibrations, but an energetically weak pattern of electrons. Now, if only we could sprinkle those microphone electrons into the electric field of this BJT transistor (I reject RAS Syndrome), they would be accelerated by the field, and if we sprinkled them in in the pattern of your voice, we could get a accelerated pattern of electrons in the same pattern as your voice but with a lot more energy, enough energy to move a loudspeaker in the same pattern to allow you to sing Never Gonna Give You Up (I just Rick Rolled you) to a stadium full of people. Well guess what a BJT does (this is the quantum mechanics part), it allows us to emit the microphone electrons (across the forward biased junction which gives the weak energy electrons a little help) into that electric field, and on the other side of the field it collects them and hands them back to us, all acceleratey. That's why once the transistor was invented we have never given it up. The quantum mechanics part means that a transistor needs to be very small, because the cloud of microphone electrons needs to use quantum mechanical probability to magically jump a very short distance from the forward biased junction into the reverse biased one. Not all of the microphone electrons get there, but we add enough energy to the ones that do that we get a stronger pattern stream than we started with. Now in a jumble I will explain several more things you need to learn: multiple transistors can be used in stages if one transistor does not amplify enough (can't remember, one stage could amplify about 1000 times?); transistor amplification is not linear, but we can use negative feedback circuits to flatten it out; or we can push the nonlinear nature in the other direction and instead of smooth amplification we can switch transistors from "off" to "on" to make digital circuits representing 0 and 1. 71.190.66.244 (talk) 21:44, 24 April 2010 (UTC)

It's a basic component that can switch and amplify

It's like If you want to be explained simply how internet work, you could be told "it's all zero and one" and If you want to understand how molecules in all the thousands types of transistors do their switch, then you gotta read thousand of books.

yes... The article from this point of view need LOOOOOTS... of work on it (not a just a clean up)--Transisto (talk) 18:51, 8 August 2008 (UTC)

I agree, this article is in a bad state. I am a computer scientist and after I read this I didn't understand any more than before I started. It's not just a case of 0s and 1s; there is no flow to the article that allows you to move from general to specific. A lot of the terminology seems to be predicated on already understanding how it works. Some of the symbols look wrong too and it appears to refer to a graph that doesn't exist. We have all different types and product codes but not clear description of what happens! Even if the various types belong in this article rather than their own (I would suggest they do not, since transistor design is so varied and there are already other articles) then the purpose/history of the types should also be clearer. Either succinct with links to deeper articles or more organised and comprehensive explanation. Clueless after reading this :( —Preceding unsigned comment added by Sam Brightman (talk • contribs) 05:32, 12 February 2010 (UTC)

Dubious graph

What's with the funny graph? The current should actually increase exponentially with VBE and won't have a corner on it as shown unless the collector voltage collapses, which means it needs to bit situated in a circuit with a supply and a load, not presented as a transistor characteristic per se. Can someone replace it with something sensible? Dicklyon (talk) 23:23, 22 February 2009 (UTC)

Any thoughts on what the graph should illustrate in order to explain whatever the article is trying to explain? Transistor data sheets tend to provide useful information about various practical modes of operation, rather than data that might help to explain transition from the linear region to the saturated region. --Gerry Ashton (talk) 23:30, 22 February 2009 (UTC)

Here's the closest I can find in commons, but it's not very good.

It was probably intended as the current in a switch configuration such as a common-emitter inverter with a resistor at the input; that would be approximately that shape. But we need to decide if we want to illustrate a circuit characteristic or a device characteristic. For talking about saturation, probably a more typical set of device curves would be good (Ic vs Vc for various Vbe, for example); that would certainly change what we say about it. Dicklyon (talk) 01:50, 23 February 2009 (UTC)

I assume we are talking about the figure Operation graph of a transistor.. This is completely bogus as shown - as Dick points out above, the collector current is an exponential function of base-emitter voltage. On the other hand if this was supposed to be output current of an idealized transistor biased into the linear region with a 4-resistor bias circuit, as shown above, then it would make some sense. But the x axis would then be "input voltage", not "base-emitter voltage", and the caption would need to say this was the response of a transistor stage, not the transistor itself. LouScheffer (talk) 04:26, 23 February 2009 (UTC)

Bit late coming to this but the article looks right to me. No collector current until V_BE reaches the switch on voltage at which point it rises linearly (strictly speaking with current rather than voltage) until the point when V_CE ≈ 0V. At this point the transistor is saturated and the current is externally limited. There is always something limiting the current. Of course if that current limiting is the resistance of copper wire or the PSU's internal resistance the current may be insanely high but the transistor is powerless to push more current through the circuit than the equivalent short circuit. CrispMuncher (talk) 18:23, 8 June 2009 (UTC).

The graph in question makes some sense with a reasonably valued collector resistor. As the base voltage rises collector current rises exponentially (the a-b segment should be bent), but the collector voltage also drops because of V_Rc + V_ce = V_CC. If V_CC could reach 0 (perfect closed switch) then I_c can go no higher than V_CC / R_C even with higher base voltage and current. This is where the trace turns horizontal.

—Preceding unsigned comment added by Circuitsmith (talk • contribs) 17:32, 13 July 2009 (UTC) The red graph shown here to the right is useful. It is a multiple trace overlay. The X axis is collector voltage. The Y axis is collector current. Each nearly horizontal red segment is for a fixed base current. This is the linear region. At each level of base current the collector current has a small dependency on collector voltage. That's why it's not perfectly horizontal. It's similar to the characteristic graph of a pentode tube. The nearly vertical part represents saturation, where the collector voltage is low and collector current current is much lower than I_b X beta. Since saturated collector-emitter voltage rises with collector current this segment is not perfectly vertical.Circuitsmith (talk) 15:52, 13 July 2009 (UTC)

I'm assuming this graph has been removed? This comment still refers to a graph which I can't see:

"It is important that the operating values of the transistor are chosen and the circuit designed such that as far as possible the transistor operates within a linear portion of the graph, such as that shown between A and B, otherwise the output signal will suffer distortion."

--David Forster —Preceding unsigned comment added by 84.43.127.183 (talk) 21:38, 9 March 2010 (UTC)

Commented out (i.e. made invisible) that text in the article. Materialscientist (talk) 22:22, 9 March 2010 (UTC)

Introduction attractiveness

What would increase general public interest and awareness ?

( Trăn-zǐs'tər )

• Visual : This cute picture introduce the notion of 3 contacts over the "famous" transistor symbol.

• Chip Density : A "fun fact" like "fingernail (12BG microSDHC) = 50bln T" ...NAND... "50bln = ~ 2 x earth circumference / ants length" (ref: Dr. Eli Harari Sandisk's Founder)

• Global ubiquity : Quick reference of global T count witch is above 2? bln T per capita
• —Preceding unsigned comment added by Transisto (talk • contribs) 14:28, 4 April 2008

In the intro of the article is the sentence "The name 'transistor' is a portmanteau of the term 'transfer resistor'" I believe this is incorrect: The actual term was 'transit resistor'. —Preceding unsigned comment added by 99.2.69.235 (talk) 01:56, 16 August 2010 (UTC)

Well, wikipedia reflects what reliable sources say. That statement is backed up by the American Heritage Dictionary, and my Oxford Dictionary says the same. Materialscientist (talk) 02:00, 16 August 2010 (UTC)

Merging of 2N2907 and such

A list of some common models in each family and links to an electronics-specific Wiki for actual articles on them would make more sense than having separate articles for 2N3906/2N2907/2Nxxxx for the silicon PNP BJT family for example. It would also be easier to manage and the content would be of higher quality simply because of the people drawn to such references. It's really not so much encyclopedic as a lookup table and should really be in a project dedicated to technical references instead of general-audience content. ("It's too complicated and also extremely redundant") Not to mention that a database may handle such information in a more easily-accessed manner for those that need that information. 24.167.39.41 (talk) 03:05, 27 February 2010 (UTC)

Thank you Google. http://www.electronics-wiki.com/Electronic_Components seems to be a good place to start. They look like they need the help, too.  :) 24.167.39.41 (talk) 03:09, 27 February 2010 (UTC)

Among the links to be avoided, WP:EL includes Links to open wikis, except those with a substantial history of stability and a substantial number of editors so peppering Wikipedia with links to the Electronics Wiki does not seem like a good idea. It really is too small, last month they had only six edits and their user list runs to only 134, all but 40 of whom are redlinks and most likely dead accounts. Even amongst the blue links, a substantial portion of them have done nothing but insert adverts for Viagra sellers!

I am completely against listing individual transistors here, far too many of them. If you are going to generate a list, it should be on its own list page. I do agree that not every transistor type deserves its own article, but many do; some types are have become so pervasive, at least in a particular period, they are almost iconic, BC108 being an example. Rather trying to merge everything here, each article should be examined on its merits. If there is more to say than simply repeating the devices data sheet (for instance, the history of the device) then it probably can be built into a Wikipedia article. On the other hand, if you think a device does not deserve an article, and never will, the right thing to do is to take it to WP:AFD rather than spoil something else with an inappropriate merge. SpinningSpark 09:19, 2 April 2010 (UTC)

I agree, many individual notable transistors deserve their own article, merging them all here would be tantamount to merging Ford Fiesta with car --UltraMagnus^speak 10:47, 21 June 2010 (UTC)

Separate pages, please. No merging. RussNelson (talk) 16:26, 27 July 2010 (UTC)

I think transistors from a certain family should all be in a single article like Transistor (2Nxxxx family). It could contain all the 2Nxxxx transistor articles currently on Wikipedia, such as 2N2222, 2N2907 and 2N3906. Most of those articles are small and would be better in a larger more comprehensive article in my opinion. -      Hydroxonium (talk) 12:05, 25 September 2010 (UTC)

You are entirely mistaken in thinking that the 2N prefix designates a family of transistors. The notation comes from the JEDEC numbering scheme where the numeral before the "N" designates the number of ports, ie terminals-1. Thus "2N" merely means a 3-terminal device and consequently all transistors are prefixed 2N under this scheme no matter how similar (or dissimilar) they actually are. SpinningSpark 12:18, 25 September 2010 (UTC)

My mistake. Thanks for the clarification. Do you think combining seperate transistor articles in to a broader article has any merit? -      Hydroxonium (talk) 11:53, 29 September 2010 (UTC)

There are indeed some families of transistors. For example, a manufacturer might have the same transistor available in plastic and metal packages intended for inserting leads through circuit board holes, plus a version intended for surface mounting. However, I am not familiar with what Wikipedia articles exist on individual transistors, so I am not able to suggest which ones should be combined. (Most of my transistor experience comes from designing individual transistors to be placed on an integrated circuit along with thousands or millions of other transistors, so I seldom had occasion to use a discrete transistor). Jc3s5h (talk) 14:19, 29 September 2010 (UTC)

There are a handful listed at Category:Commercial transistors and all the 2Nxxxx are listed as stubs. I'm just wondering if combining them is valid. -      Hydroxonium (talk) 14:51, 29 September 2010 (UTC)

Yes, some of those certainly seem to be mergeable, although I am not particularly familiar with them. As well as the same basic type in different packages as pointed out above (although those would tend to have the same root part number) there are other ways families are formed. Some types are made to be used as matched pairs of NPN and PNP transistors in Class B amplifiers, BD131 and BD132 are examples. There are also families of basically the same transistor in different qualities: an example of this is BC107, BC108 and BC109 which all come off the same production line, but the higher gain ones have BC109 stamped on them. This last family was at one time so ubiquitous as the low-frequency, low-power transistor that it certainly deserves an article. SpinningSpark 09:22, 1 October 2010 (UTC)

Labels lost from amplifier circuit

The paragraph under "Transistor as an Amplifier" refers to labels V(in) and V(out) in the amplifier circuit diagram, but they were lost when that diagram was replaced on 14 February 2007. The original diagram is more instructive. [I came here to learn about transistors so I have no business trying to edit anything in this page.] — Preceding unsigned comment added by Klossner (talk • contribs) 22:40, 14 December 2010 (UTC)

WP:ENGVAR

It seems to me that this article has been pretty consistently in American English since this diff sorted it out from a more mixed existence back in 2004. I don't agree that we should be looking back to who first added a word to the stub in 2002 to decide what language to use. Dicklyon (talk) 00:45, 24 January 2011 (UTC)

I think it is quite terrible that so many experienced editors (including myself) have got into an edit war over something so tangential. The original edit was done by an IP who clearly was not aware of the guidelines and I reverted it purely on those grounds (that it was not referenced to the guidelines). Everything else should have gone to the talk page first before any further editing. Dicklyon, surely the article got into a mixed state because it had been added to by American editors after it had been started in a British spelling system. Someone coming along and arbitrarily picking a spelling system without consensus is no more acceptable. You might disagree with looking back to the earliest edits but that is what WP:ENGVAR calls for. Frankly, I would probably support Wikipedia having a specified spelling style but that is not what we currently have in the guidelines and individual articles are not the right place to argue for it. As far as I can see the earliest editor to unambiguously adopt a spelling style was here (note colouration). The article at this stage was beyond a stub and the contribution is substantial, meeting the WP:RETAIN guideline. SpinningSpark 19:37, 27 January 2011 (UTC)

Well, I did study the history, and it appeared to me to be solidly American for many years, with a few recent Britishisms. The IP edit you reverted was this one; so we should look for what led to it. It came in in May 2010, here. The only other Britishism I notice at that time is "standardised"; no "behaviour" but two "behavior"s. The sentence "Prior to the development of transistors, vacuum (electron) tubes (or in the UK "thermionic valves" or just "valves") were the main active components in electronic equipment" suggests a US perspective in use. So it appears to me that the IP you reverted was doing the right thing, trying to make the article more consistent per WP:ENGVAR; just didn't go quite far enough. Dicklyon (talk) 06:00, 28 January 2011 (UTC)

By the way, why is amongst being considered a Britishism? It is a perfectly good word. SpinningSpark 19:45, 27 January 2011 (UTC)

Why is it so important to cultivate these delibrately archaic spellings? Is this the same spirit that puts "Ye Olde Touriste Shoppe" on signs? --Wtshymanski (talk) 21:11, 27 January 2011 (UTC)

There are dictionaries that will tell us what is archaic and what is confined to a particular part of the English-speaking world. My American Heritage Dictionary 3rd ed. says "a•mong [pronunciation omitted] also a•mongst" with no notations about being archaic or regional. Jc3s5h (talk) 21:46, 27 January 2011 (UTC)

I don't need a dictionary to know that "amongst" is rarely used, and sounds either foreign or archaic to the typical American who is used to "among". Might as well stick with the more common. Dicklyon (talk) 05:50, 28 January 2011 (UTC)

Possibly a stupid question

"when electrical contacts were applied to a germanium crystal, the output power was larger than the input."

This seems very misleading -- I assume that two different power measurements are being performed, and the device didn't suddenly get very cold, or violate thermodynamics? That is to say, as it reads now, it seems like the device is creating energy out of nowhere. Could it be fixed by citing the work in question and explaining which power outputs were measured (I assume c-e power, not b-e? (my electronics is terrible)) 86.148.6.114 (talk) 23:12, 23 August 2011 (UTC)

First silicon transistor

Someone editing under the name Tanenbaum says that Morris Tanenbaum made the first diffused silicon transistor in January 1954. The Siffert book cited in the article says that TI announced their silicon transistor in May 1954. The Tanenbaum physics paper was published in 1955. "Makers of the Microchip: A Documentary History of Fairchild Semiconductor" by Christophe Lacuyer, page 10, says March 1955, Tanenbaum, diffused "mesa" transistor - but the physics paper has "grown junction" in the title. "Electronics: The Life Story of a Technology" by David L. Morton says Tanenbaum, diffused transistor, early 1955. My 1956 "Handbook of Semiconductor Electronics" by Hunter pays no attention to trivia like who invented the transistor, but does list the 1955 Tanenbaum grown junction paper in the bibliography.

So, which silicon transistor (diffused or grown) was the first, which one did TI announce in May 1954, obviously they'd been working on it for some time before announcing it, and which one did Dr. Tanenbaum create, and when? --Wtshymanski (talk) 23:27, 1 October 2011 (UTC)

And "Managing Technological Innovation: Competitive Advantage from Change" by Frederick Betz pp. 213-214 tells the story of how TI demonstrated the temperature range of their silicon transistors at a conference. What is "invention"? Lab prototype or production unit? --Wtshymanski (talk) 23:37, 1 October 2011 (UTC)

In 1943, Herbert Mataré created a point contact silicon "duodiode" at Telefunken that worked at 10 GHz to build a mixing receiver/detector for "Rotterdam" RADAR systems from the british royal airforce. He placed the two point contacts very close together in order to get the same white noise from both diodes. With this device, he discovered behavior that could not be explained with two separate diodes. This is the basic for later point contact transistors and it was build on silicon. The two metal point contatcs have been placed on polycrystalline silicon evaporated on a graphite rod. --Schily (talk) 14:26, 5 October 2011 (UTC)

Image repeated

This figure is repeated twice in succesion with no good reason: "Through-hole transistors (tape measure marked in centimetres)" — Preceding unsigned comment added by 79.71.101.84 (talk) 10:39, 30 September 2011 (UTC)

I agree. This is a legacy from the old Discrete transistor page which was merged into this one. Each of the similar images had only four examples, I found a better replacement on Wikipedia commons which had seven distinct representative examples. I'll add one of the images to the semiconductor package page which lacks a discrete transistor example in its gallery. Wbm1058 (talk) 00:04, 4 December 2011 (UTC)

Suggest merge

Discrete transistor could be merged here, it has little content that isn't already discussed here. --Wtshymanski (talk) 22:48, 10 September 2011 (UTC)

That was done just before the end of September Wbm1058 (talk) 01:07, 4 December 2011 (UTC)

Photo of CP431 is not a transistor

The picture of the TO92 package of a CP431 in http://wiki.riteme.site/wiki/File:Electronic_component_transistors.jpg is not a transistor, but rather a shunt regulator - more closely related to a Zener diode... — Preceding unsigned comment added by 70.57.19.180 (talk) 19:06, 1 October 2011 (UTC)

I moved that picture to the Semiconductor package article, so as long as they're all made with semiconductors, we're good! Wbm1058 (talk) 01:26, 4 December 2011 (UTC)

Undefined terms in "Transistor as a switch" section (IC, IB)

The section "Transistor as a switch" is unreadable because it refers to values I_C and I_B that it does not define. Additionally, it's quite hard to piece together the meaning of the other symbols it uses (VRB, VCC, ICE etc.) because their definitions have to be inferred from the diagram. Could someone who understands it please clean it up a bit so that it defines its terms a bit more clearly? Nathaniel Virgo (talk) 14:30, 20 December 2011 (UTC)

You're right. How is it now? Equations are only useful if you're assigning your students calculation problems. --Wtshymanski (talk) 20:09, 20 December 2011 (UTC)

Vandalism?

This looks like vandalism to me:

"Schottky transistor i like men"

Some of the editors may want to remove that; thank you — Preceding unsigned comment added by 174.109.21.63 (talk) 22:27, 10 January 2012 (UTC)

This is a database glitch (edit reverted but shows up in the article - to me as well). I have deleted the offending article version that fixed the problem, at least on my PC. Materialscientist (talk) 22:44, 10 January 2012 (UTC)

"Fundamental building block" vandalism

This recent vandalism got me thinking if this should be changed. I agree that it is a fundamental building block, but perhaps not the fundamental building block in electronic devices. I mean, you're not going to get much done without a resistor or capacitor.--Asher196 (talk) 21:14, 29 January 2012 (UTC)

Actually, most transistor-based stuff doesn't use anything but transistors. Resistance and capacitance are parasitics that have to be dealt with, but resistors and capacitors are not used as building blocks. In DRAMs, or course, capacitors are important, and in SRAMs resistors are often used, but these are not the typical case. Even in analog circuits resistors are typically absent except as parasitics. Dicklyon (talk) 21:58, 29 January 2012 (UTC)

"Bipolar Junction Transistor"

The paragraph ending in "It is typically greater than 100 for small-signal transistors but can be smaller in transistors designed for high-power applications." gives the impression that all BJTs have a beta of a hundred with the exception of power devices. There are other specialized classes of transisors that have (or have had) low gain, such as RF and high voltage. I suggest changing the sentence to "It is typically greater than 100 for small-signal transistors but can be smaller in transistors designed for specialized applications such as high power or R.F." [User:acmefixer] 2012 May 10 — Preceding unsigned comment added by 208.127.8.215 (talk) 10:30, 10 May 2012 (UTC)

Sounds fine to me, go ahead if you want. Except that we generally do not use periods in abbreviations. SpinningSpark 14:02, 10 May 2012 (UTC)

Principle

There's nothing to contest. This is not politics. What, are we going to Vote on matters of science now.

Amanbir Singh.

— Preceding unsigned comment added by 117.199.109.185 (talk) 14:40, 17 October 2012 (UTC)

The original revert was not because your information was incorrect, it was that it was unsuitable for the lead section. The lead section needs to be simple at to the point: your info is more at home later on in the article. Please leave the page as it is until we have resolved this issue. – Richard BB 14:46, 17 October 2012 (UTC)

• You (the IP) are supposed to stop the edit war while you discuss the reason your change was contested. But you have continued to remake your change while openly refusing to discuss it, so I have semi-protected the article to prevent you editing it. -- Boing! said Zebedee (talk) 14:50, 17 October 2012 (UTC)

What do you want? Speak? — Preceding unsigned comment added by 117.199.109.185 (talk) 14:55, 17 October 2012 (UTC)

Please see my last edit. Materialscientist reverted your edit as it is not suited for a leading sentence. That's not to say it's a bad edit, it just means that the WP:LEAD isn't the place for it. If you disagree, please discuss it with Materialscientist rather than edit warring. – Richard BB 15:05, 17 October 2012 (UTC)

It's pretty much nonsense anyway. I'm treating it as just vandalism. SpinningSpark 15:17, 17 October 2012 (UTC)

Good faith changes are never vandalism, even if they are inaccurate, so please don't treat them as such - see WP:VANDALISM for what actually constitutes vandalism, (Though as an admin, you really should know that!) -- Boing! said Zebedee (talk) 15:25, 17 October 2012 (UTC)

Vandalism can include a bunch of buzz words to make it seem plausible, especially to Wikipedia editors who lack subject matter expertise. I was leaning toward the hypothesis that this was deliberate vandalism disguised to create extra confusion. The comment "i want to kick some english ass" serves as conclusive proof the edit was intentional nonsense. Jc3s5h (talk) 15:55, 17 October 2012 (UTC)

No, that is not conclusive proof of anything of the sort. It's proof that he's angry and combative, perhaps, but not that his proposed content change is vandalism. -- Boing! said Zebedee (talk) 16:54, 17 October 2012 (UTC)

@Boing (after e/c) I understand that perfectly, you don't need to explain policy to me. The edit was technobabble masquerading as good faith. My opinion is we are being trolled. I would be interested in what you thought

"It is based on the principle of dual resistance, tending to infinite and zero, and hence behaving as an insulator and a conductor, based on its vector alignment in a circuit. It is a discrete form of electrical filter circuits."

actually means. In any case the editor has not presented any kind of rational argument for it - only threats. SpinningSpark 16:00, 17 October 2012 (UTC)

I think he's just talking about switching, to be honest, but does not have good command of technical English and is writing over-elaborate prose - "dual resistance, tending to infinite and zero" sounds like "on and off" to me. Apologies if I sounded a bit sharp, but we should not assume this is vandalism or trolling. (I'm certainly not supporting the addition, btw, and yes he would need to provide a source) -- Boing! said Zebedee (talk) 16:08, 17 October 2012 (UTC)

You really think a semantic analysis of this garbage is possible? You might parse the first part as "behaves as on an on-off switch", but then what are we to make of the "vector alignment" of this switch? And how does that make it a filter? I was not demanding sources, we have not got anywhere near that stage, I only pointed out the editor has not explained their edit - and that's probably because they do not actually know anything. SpinningSpark 16:34, 17 October 2012 (UTC)

Yes, I know that you pointed out the editor has not explained his edit, and it might indeed be because he doesn't know what he's talking about (but it might also be because his English is poor - he's called "Singh" and is posting from India - and that's what my suggestion that part of it sounds like it might mean something is about). All I am saying is that the paucity of explanation does not make it vandalism and it should not be treated as vandalism. That is all. -- Boing! said Zebedee (talk) 16:51, 17 October 2012 (UTC)

It's not poor English, it is completely made-up bollocks. SpinningSpark 17:54, 17 October 2012 (UTC)

Sigh, you know what? After his latest additions to my talk page, I think you might be right - I think your judgment was better than mine on this one. -- Boing! said Zebedee (talk) 18:52, 17 October 2012 (UTC)

Is / must be

"the resistor must be chosen" implies an imperative on the designer who is quite free to choose an inadequate resistor.

"the resistor is chosen" simply states a fact about the design. Constant314 (talk) 18:49, 21 November 2012 (UTC)