Talk:Propagation delay

Physics Low‑importance

	Physics portal This article is within the scope of WikiProject Physics, a collaborative effort to improve the coverage of Physics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.PhysicsWikipedia:WikiProject PhysicsTemplate:WikiProject Physicsphysics articles
Low	This article has been rated as Low-importance on the project's importance scale.

Computing: Networking Low‑importance

	This article is within the scope of WikiProject Computing, a collaborative effort to improve the coverage of computers, computing, and information technology on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.ComputingWikipedia:WikiProject ComputingTemplate:WikiProject ComputingComputing articles
Low	This article has been rated as Low-importance on the project's importance scale.
	This article is supported by Networking task force (assessed as Mid-importance).
	This article is supported by Computer hardware task force (assessed as Mid-importance).

Electronics Mid‑importance

	Electronics portal This article is part of WikiProject Electronics, an attempt to provide a standard approach to writing articles about electronics on Wikipedia. If you would like to participate, you can choose to edit the article attached to this page, or visit the project page, where you can join the project and see a list of open tasks. Leave messages at the project talk pageElectronicsWikipedia:WikiProject ElectronicsTemplate:WikiProject Electronicselectronic articles
Mid	This article has been rated as Mid-importance on the project's importance scale.

Is that a typo?

"Wires have an approximate propagation delay of 1 ns for every 6 in of length." should that be inch instead of in? I fail at finding the information in the referenced book. — Preceding unsigned comment added by Billiska (talk • contribs) 10:54, 26 December 2011 (UTC)[reply]

Removed section about metastability

The following section was removed:

Often one logic gate is connected to another that is connected back to the first. When an invalid input is applied to such a system, the amount of time from when the external inputs to the system become stable and valid to the time the output of both logic gates become stable and valid can be far longer than the normal propagation delay. This is the problem of metastability in electronics.

Looping back gates generates latches and is strongly discouraged, but possible. Invalid input relates to observance of setup and hold timing requirements of a synchronous flip-flop. Failure to observe these requirements does precipitates metastability, which has nothing to do with simple, unclocked logic. Michagal 16:52, 15 March 2007 (UTC)[reply]

Typical propagation delay?

I think this article should give some idea as to what the typical propagation delay for a logic gate is. At least the approx order of magnitude - i.e. is it a few ns / ms etc? And does it vary much between different types of logic gates? --Vclaw 23:53, 12 October 2007 (UTC)[reply]

I would like info regarding how propagation delay relates to time rise and time falls and other delays associated with electronics. Jksgvb (talk) 05:30, 10 August 2009 (UTC)[reply]

Different definition of Propagation Delay

"Often this refers to the time required for the output to reach from 10% to 90% of its final output level when the input changes."

Another definition (according to http://books.google.de/books?id=q-PwBNuAEVYC&dq=definition+propagation+delay&hl=de&source=gbs_navlinks_s, http://www.ece.msstate.edu/~reese/EE4743/lectures/timing/timing.pdf and many others):

Tplh -- time between a change in an input and a low to high change on the output. Measured from 50% point on input signal to 50% point on the output signal. The ‘lh’ part (low to high) refers to OUTPUT change, NOT input change

Tphl -- time between a change in an input and a high to low change on the output. Measured from 50% point on input signal to 50% point on the output signal. The ‘hl’ part (high to low) refers to OUTPUT change, NOT input change

I think this definition is more common and should therefore be mentioned in the article. — Preceding unsigned comment added by 141.3.72.109 (talk) 09:14, 7 June 2013 (UTC)[reply]

Proposal about definitions

Speaking of definitions, they are not directly related and thus shouldn't belong in a single article. The networking, electronics, and physics definitions have more appropriate places, as specified below:

The Networking section should be merged with and become a new section in the article Transmission delay, and a page Propagation delay (networking) redirect there.
The Electronics section should be moved and renamed to Gate delay as that is by far a more common term, and a page Propagation delay (electronics) redirect there.
The Physics section should be merged with and become a new section in the article Velocity factor, and a page Propagation delay (physics) redirect there.

Note: as for this page itself, it would be best to make it redirect to Gate delay and appropriate hatnotes added to link to the other definitions. A dab page would not be necessary. <<< SOME GADGET GEEK >>> (talk) 01:01, 4 March 2015 (UTC)[reply]

Coping with propagation delay?

The article mentions that propagation delays can cause problems in electrical circuits, but provides no insight into how this problem can be managed. Surely there must be a way to do this, as VLSI would be unweildy without such consideration. Possibly many ways. Can these be mentioned in the article? — Preceding unsigned comment added by 70.247.168.209 (talk) 05:11, 6 August 2015 (UTC)[reply]

Split proposal

A split proposal banner was added in March 2015. I don't see any discussion of this proposal so I'll start one.

Oppose for now. The three types of propagation are related to the same basic electromagnetic properties. Since there is a common mechanism and the article is not long, I don't see a compelling reason to split at this time. ~Kvng (talk) 00:01, 14 December 2015 (UTC)[reply]