Talk:IC power-supply pin

I think this article should be moved to something like IC power supply pins and extended to cover them equally. what do other people think? Plugwash 21:13, 16 August 2005 (UTC)

Sure. - Omegatron 21:16, August 16, 2005 (UTC)

History (clipped)

V_CC (note: lower case is sometimes used instead of subscript, e.g. "Vcc") is an abbreviation for "common-collector voltage". V_EE refers to similar pins on devices with common-emitter connections. TTL logic usually uses a bipolar junction transistor process, so uses the V_CC–V_EE labeling. Since NPN transistors are the more common variety V_CC became positive and V_EE negative.

Meanwhile NMOS used V_DD (drain), and V_SS (source) labels for positive and negative respectively. This notation continued with CMOS even though it has drains connected to both power supply rails. As logic families have evolved the power supply pin labeling may not have much to do with the connections to the actual transistors.

Why on earth has someone clipped the history section? Editors are way too overzealous here. This is important information.

Alternative explanation for double letter notation

I have always belived that the double letter notation is to make it simular to all the other notations in transistors. For instance, Vds, meaning the voltagedrop between drain and source. Vdd, Vss, Vcc and Vee are voltages that isn't actually relative to anything which is different from Vd, Vs, Vc and Ve that all are relative to ground. So you can't just drop a letter, and it isn't relative to the other terminals. Therefor, it is my belife, that it simply means drain-drain, source-sourc etc. which means that it is relative to whatever you want it to be relative to.

This might not be the best explaination. It might be due to me being wrong, or that I am correct, but not very good to express myself in english. However this a topic that is hard to find the actually facts about. I just took part in a lecture where the professor didn't know the answer, and I am a master of science in hardware design myself.

129.241.206.21 16:21, 8 February 2007 (UTC)Mr.Kalle

NC means "not connected"

Someone coming here is probably looking for help understanding an IC connection diagram. In that context, it would be good to include something about what "NC" means. —The preceding unsigned comment was added by 190.56.56.246 (talk) 13:32, 17 April 2007 (UTC).

Diagram

Added a diagram, removed {{reqdiagram}} tag. Tswsl1989 13:50, 15 June 2007 (UTC) (Update: forgot to tl template Tswsl1989 07:48, 20 June 2007 (UTC))

Generic IC Image Incorrect?

The image of the generic IC seems to have two positive supply inputs (Vcc and Vdd). I assume one of these should be a negative supply input (probably change Vdd to Vss or Vee). —Preceding unsigned comment added by 58.174.32.2 (talk) 00:19, 22 November 2007 (UTC)

I noticed this too - it also seems wrong to me. Should it be deleted? Hithisishal (talk) 06:17, 31 January 2008 (UTC)

I just noticed this. It's rather impractical for an IC to have two positive rails, so while it is theoretically a real IC, it will also confuse people. —Preceding unsigned comment added by 128.12.119.156 (talk) 14:34, 16 May 2008 (UTC)

Ground

Something called V_gnd often appears in circuit diagrams as well. Can that be added here? Also, could someone explain why there is negative voltage rather than ground? — Preceding unsigned comment added by Skysong263 (talk • contribs) 16:28, 24 October 2011 (UTC)

Notability

• I'm happy with this article; first hit on "v+ v-". Keep! Joshua Jonathan (talk) 15:18, 17 October 2012 (UTC)

• Notability is good. People should not able tag and run with out a write up on why they tagged! Tag will be removed. Telecine Guy 20:51, 9 January 2013 (UTC)

Really nice page! Clearly and concisely covers the subject. One could run quite a few Google searches without acquiring this content. — Preceding unsigned comment added by 174.100.201.44 (talk) 14:46, 30 April 2020 (UTC)

Other letters?

Anyone know what might be the derivation of other double subscript letters sometimes used with V? For example, I've seen Vff in a few rare places, and there's never any clear indication of what it could be other than there being a definition of what it needs to be. In some cases it seems to be a duplicate of Vdd and/or Vee but that's as close as I've got. In general it seems to just be thrown in without any warning or explanation, with the implication that if you're using it you already know what it means (maybe the answer is buried somewhere in an electrical engineering degree textbook which hasn't ever appeared online?). Googling around brought me here...

(There is also e.g. Vaa, as well as Vgg for FETs, but the latter is at least is clear as the - usually variable - supply for the Gate) 80.189.129.212 (talk) 12:18, 26 August 2018 (UTC)

VIN,VA,VDD,GND

30, 2023, 13:28 - «This paragraph is specifically about the ground pin. The reverted changes confused the discussion.»

@Constant314: Well I would appreciate much if we keep few words on difference between these. Thanks!

AXONOV (talk) ⚑ 16:57, 2 June 2023 (UTC)

Hello. Thanks for using the talk page to discuss these changes. I have no problem with having the information there. I think that if it is in a separate paragraph that will be fine. The ground pin is, in some ways, the most special of all pins. I would like to have it discussed in its own paragraph, or at least in a separate sentence. Constant314 (talk) 18:22, 2 June 2023 (UTC)