Talk:7400-series integrated circuits

message: Is it just me or does the article look a wee bit like someone snuck some Potato Semiconductors advertisement in?  —Preceding unsigned comment added by 131.188.212.202 (talk) 13:05, 30 January 2008 (UTC)
replies: text: I assume this ad is gone now and this comment can be removed? I don't see anything about potato anymore. JettaMann (talk) 13:26, 8 November 2010 (UTC)
thread_title: Advertisement

message: The opening sentence reads "The 7400 series of TTL integrated circuits are historically important as the first widespread family of IC logic". With no definition of what IC logic is. Integrated Circuit? This should be defined for the non-expert. Or at least linked. Bilz0r 23:54, 3 September 2007 (UTC)
thread_title: IC logic

message: Could someone do more research on the different families of logic? http://www.ti.com/ (http://focus.ti.com/logic/docs/technologyfamily.tsp?templateId=5985&navigationId=11386&DCMP=TIHomeTracking&HQS=Other+OT+home_p_logictechfam) has an extensive list of logic families.  Also, additions like the 'A' prefix sometimes means Advanced, and the 'H' suffix means bus hold, etc. could be improved. Mhowell 14:25, 17 October 2005 (UTC)
thread_title: Logic Families?

message: The main page states that the 7400 was available in 1962.  I believe this is incorrect.  I'm pretty sure that it
was introduced around 1966-1967, but I don't have an authoritative reference.  Note that there were other TTL
parts before the 7400 series (e.g., the Motorola MTTL 4000 series, not to be confused with the CD4000 CMOS series).  --Brouhaha 15:23, 29 Sep 2004 (UTC)
thread_title: Introduction date and early pricing

message: I removed the following paragraph as it has NOTHING to do with 7400 series TTL, which was not used in the Minuteman II:
  The computer for the Minuteman II missile used integrated circuits in such large quantities  
  that the prices fell to only $15 per package of four gates, paying for the difficult new lithographic assembly
  lines, and enabling the sharply-reducing prices of the modern digital computer.
--Brouhaha 23:49, 4 Oct 2004 (UTC)
thread_title: (Non-) use in Minuteman II missile

message: From the diagram, am I correct in thinking this product had only 4 transistors in it?
:MSTCrow 18:30, 17 March 2006 (UTC)
replies: text: No, the diagram shows 4 NAND gates. Each gate is implemented in typically 4 transistors (a few more for AND, NOR, OR gates etc) for a total of 16 transistors in the 7400. Four of these transistors has two emitters in it, so you might want to count those as say 1.3 transistors (4 connections to the usual 3). An eight input NAND gate (7430) has just 4 transistors, but one of these has 8 emitters (which you might want to count as 10/3, so only about 6.3 transistor equivalents in that one. These are the SSI chips (small scale integration). Things like the 7490 counter are called MSI (medium scale integration), they have maybe a hundred transistors in them. --Mike Van Emmerik 22:30, 17 March 2006 (UTC)
thread_title:  Transistor Count? 

message: Do the pictures of the homebrew projects add anything to the article? They seem irrelevant to me. -- Mikeblas 11:52, 26 March 2007 (UTC)
replies: text: Yes somewhat irrelevant, and also in the TTL article. It would be natural with, say, a picture of an older (all TTL) mini-computer or IBM-PC board, along with one that shows surface mounted 74-series chips supporting large ICs (and/or usage in consumer electronics). I guess a couple of current pictures could as well be kept though (as "curiosa"), or used in other appropriate articles. HenkeB 07:55, 28 April 2007 (UTC)
replies: text:  I've removed them, then. -- Mikeblas 19:14, 9 June 2007 (UTC)
thread_title:  pictures 

message: Um, so who introduced the 7400 series? - MSTCrow 16:56, 14 June 2007 (UTC)
replies: text: Texas Instruments, I think. -- Mikeblas 16:57, 14 June 2007 (UTC)

text: But see Transistor-transistor logic article for the history of TTL; which cites the Computer Museum web site. TTL was invented in 1961, and although TI made the biggest family of parts, there were many manufacturers in the TTL business in the early years (including Westinghouse- remember Westinghouse?). TTL and 7400 series weren't quite synonomous. --Wtshymanski (talk) 14:41, 21 April 2008 (UTC)

text: FWIW...back in the 80's when I was a hobbyist, I read that Texas instruments originated the 7400 series for our space program.  — Preceding unsigned comment added by 67.241.83.46 (talk) 00:40, 3 September 2011 (UTC)

text: I too was wondering (2019-4-7) what the origin of the 74 prefix was; I'd wondered if it was the year 1974, but seems it was around in the late '60s, so not that. Could be the fourth variant in the 7000 series (see section below), but it's not clear whether that is the case, and even if it is, it would beg the question of where that "name" came from.  — Preceding unsigned comment added by G6JPG (talk • contribs) 15:26, 7 April 2019 (UTC)
replies: text:  1) The 74 prefix doesn't have anything to do with the year 1974, because in the "Further Reading" section there are 7400 series parts in the 1967 Texas Instruments catalog and 1971 book. 2) Texas Instruments SN7400 family is commercial (and industrial) temperature range parts, SN5400 family is similar parts in military temperature range parts.  3) Most likely 7400 series wasn't used in space, instead 5400 military parts would be more likely.  4) See Transistor–transistor logic#History for more historical information.  • Sbmeirow • Talk • 18:29, 7 April 2019 (UTC)
thread_title:  7400 Originator 

message: I found this interesting story about an early use of the 7400 series in a mixed analog-digital application.  There might be something in there worth mentioning in the article.  -- RoySmith (talk) 17:05, 14 June 2007 (UTC)
thread_title:  Some early history 

message: In the early 1980's, I ran across a parts bin with other 7000 series devices. Might have been 7200s or 7300s, I can't remember. Anyway, we pried the tops off of some of these, took some photomicrographs and determined these were discrete logic devices analogous to 7400s. Later, I found some some data books (maybe TI, can't remember) that confirmed these were DTL devices. It seemed that the 7400 series was the latest (and most successful) of these 7000 series. We all know the limitations of DTL, so that's what probably led to 7400 TTL devices.
Also, TI had some 7500 devices as I recall. I didn't have any docs on these, but I did see them used on some large wire wrapped logic boards in the 70's and 80's. The ones I remember were 8 pin DIPs, looked liked line drivers, level converters, or related logic interface.
What about 7600s? The classic SN76477 and SN76488 come to mind.
Does anyone have any more info on this? Madhu (talk) 21:50, 31 December 2007 (UTC)
thread_title:  Other 7000 series logic families 

message: It's overstated to say that 7400 series TTL chips were standard components for 40 years in many products besides computers.  Hardly anything had 7400 chips in it in 1968 *besides* computers.  Hardly anything *today* has 7400 series chips in it. Even at its peak popularity, it was not hard to find  for example especially consumer electronics that had no TTL in it. The phrase irritates me because it's vacuous and content-free and not even particularly descriptive, and not true. --Wtshymanski (talk) 16:15, 14 January 2008 (UTC)
replies: text: Well, I can live with your edits, however, the text didn't say that exactly, "...standard-components for more than 40 years, and seen use in many types of products and equipment besides computers." was intended to state two separate things: (1) the 7400 series has defined standard functions and pin-configs. since long, and, (2) the chips have been used in many other apparatus than computers. Hardly untrue. / HenkeB (talk) 17:03, 14 January 2008 (UTC)
replies: text: I just hit a few of my books; for example Don Lancaster refers to the RTL family, and ECL was also made before 7400 series.  "Widespread"is difficult to nail down. --Wtshymanski (talk) 17:31, 14 January 2008 (UTC)
thread_title: Standard component

message: I'm not sure exactly where (or if) it belongs in the article, but there's some interesting information about failure modes of 7400 (and other) logic chips used in early video games at . -- RoySmith (talk) 20:57, 14 January 2008 (UTC)
thread_title:  Failure statistics 

message: -- RoySmith (talk) 21:00, 14 January 2008 (UTC)
thread_title:  Sources for references... 

message: Can't find any reference to a "6400" industrial series in my 1973 first edition  TI TTL handbook, nor in my 1975 edition of the Don Lancaster book, nor in my 1988 edition of the TI databook. Even a  Google search only turns up this Wikipedia page and its hangers-on.  I'm taking it out till someone can find a reference. --Wtshymanski (talk) 02:36, 21 April 2008 (UTC)
replies: text: It seems there was enough interest in the 6400 series parts that Mullard had a line of interchangeable TTL parts to substitute for them. They must have been sold for a very short time because they don't appear in my TTL Data Book - but the Mullard data sheets are dates 1970, just a little older than my book. So, it's going back in, with a reference this time. --Wtshymanski (talk) 00:02, 17 May 2008 (UTC)
thread_title: 6400 series

message: This article makes me feel nostalgic for the first chip I ever bought, a 7400. Gvanrossum (talk) 00:09, 2 May 2009 (UTC)
thread_title: Nostalgia

message: Yet Another Slow-Motion Edit War:  The recent editing history at :7400 series shows that some of the editors here are currently engaged in an edit war. 
Being involved in an edit war can result in you being blocked from editing.
Undoing another editor's work—whether in whole or in part, whether involving the same or different material each time—counts as a revert.  Also keep in mind that while violating the three-revert rule, which states that an editor must not perform more than three reverts on a single page within a 24-hour period, often leads to a block, you can still be blocked for edit warring—even if you don't violate the three-revert rule.
To avoid being blocked, instead of reverting please consider using thuis article's talk page to work toward making a version that represents consensus among editors. See BRD for how this is done.  --Guy Macon (talk) 19:22, 27 April 2013 (UTC)
thread_title:  Yet Another Slow-Motion Edit War 

message: Hi ,
No objection to moving the article to a more descriptive name, but I would not combine this article with List of 7400 series integrated circuits since that list is rather large and often not of interest for readers looking for an overview of the 7400 series.
Drahtlos (talk) 16:06, 13 July 2018 (UTC)
replies: text: I agree with Drahtlos.  The title change is fine, but I wouldn't do the merge.  -- RoySmith (talk) 16:08, 13 July 2018 (UTC)
thread_title:  Merge with [[List of 7400 series integrated circuits]] 

message: I took a stab at overhauling the intro section.  It might need some elegant wordsmithing help.  • Sbmeirow • Talk • 11:23, 23 July 2019 (UTC)
replies: text: I think the latest edits to the lead are very much an improvement. Good job!  --Guy Macon (talk) 12:46, 23 July 2019 (UTC)
replies: text:  Thanks. Others are welcome to improve or expand it. • Sbmeirow • Talk • 13:50, 24 July 2019 (UTC)

text: While designed as a family of digital logic, some TTL chips were used in analogue circuits, such as Schmitt triggers. Like the 4000 series, the newer CMOS versions of the 7400 series are also usable as analogue amplifiers using negative feedback (similar to operational amplifiers with only an inverting input).  However, this type of circuit suffers from significant harmonic distortion and shortened component life.  As the parts are not designed to operate in the partially on/off region except when switching states, heat buildup can be severe.
I was unable to find any source for using logic chips as analog amplifiers, although I have heard of it and did some experiments with it years ago (nothing that went into production, just fooling around in the lab). See Talk:7400-series integrated circuits#Need help finding citation for NAND gate in analog mode.
Also an op-amp based Schmitt trigger is really more of an example of using an analog chip to do a digital function than it is an example of using a digital chip to do an analog function
Didn't some early personal computers use logic outputs to drive speakers? If we can find sources that might be a better example of using digital to do the job of analog.  --Guy Macon (talk) 12:46, 23 July 2019 (UTC)

text: Don Lancaster in "TTL Cookbook" says on pp. 169-170 that while you could theoretically bias a gate into the linear region, you'd rather not rely on it.  He does give an example of a ring oscillator made of open collector gate. TTL crystal oscillators were present in some personal computers; I have schematics for the obscure Ibex 7150 and the rather more popular Osborne 1, and both of them use crystal oscillators made of a TTL gate. (The Osborne had bipolar transistors to drive the non-TTL-compatable clock input of the Z80, the Ibex worked OK at 2.5 MHZ driving the Z80 clock from the TTL oscillator but to work reliably at 4 MHZ the 7406 had to be changed to the HCMOS "pin compatible" equivalent).   Don't know what a Kaypro used.  The IBM XT used a real dedicated clock generator chip. --Wtshymanski (talk) 23:32, 23 July 2019 (UTC)
replies: text: And here is another that says no to driving a speaker with TTL.  Not that someone else might not have done it anyway... Dicklyon (talk) 00:21, 24 July 2019 (UTC)

text: This guy says "Combining L-C tuned circuit with TTL inverter gives low-cost bandpass amplifier for use as frequency multiplier, or i-f amplifier. Q of feedback path can be modified ..." Dicklyon (talk) 00:27, 24 July 2019 (UTC)

text: And here's one showing a Schmidt trigger (and other stuff) made with TTL NAND gates. Not really a good idea, but it can work. Dicklyon (talk) 00:30, 24 July 2019 (UTC)
replies: text: I should also note that I added "citation needed" tags to this section a while back, and nobody's found citations for this yet.  Maybe, if nobody can come up with good citations, we should just drop it completely.  -- RoySmith (talk) 15:03, 3 August 2019 (UTC)
replies: text: I say nuke it. Despite the fact that I actually did this in the lab (unbuffered 4000-series CMOS maybe kind of work if the phase of the moon is right, 7400-series H and HC don't work at all) the sources simply do not show that this was ever a significant use. --Guy Macon (talk) 22:34, 7 September 2019 (UTC)
thread_title:  Revised lead 

message: The speeds given seem unreferenced and some technologies missing. See http://www.ti.com/lit/sg/sdyu001ab/sdyu001ab.pdf --Kitchen Knife (talk) 14:09, 4 September 2019 (UTC)
replies: text: and this Also by TI some different abbreviations http://digsys.upc.es/csd/units/Elect/TI_Digital_Logic_Families.pdf --Kitchen Knife (talk) 20:16, 7 September 2019 (UTC)
thread_title: Speed

message: Is this a fa,ily that needs adding https://www.ti.com/lit/an/scea069a/scea069a.pdf --Kitchen Knife (talk) 21:38, 25 June 2022 (UTC)
replies: text: This parts list is friend to all integrated circuits. As long as it has a "7" or a "4" somewhere in its part number and is some kind of digital IC, you'll not find anyone denying it a home here.  Parts lists articles are best when they have lots of parts in them, after all. The more the merrier. --Wtshymanski (talk) 02:26, 7 July 2022 (UTC)
replies: text: This isn't the parts list. Its the description of what 7400 is and the technology in which it is implemented and the HCS technology is not mentioned. --Kitchen Knife (talk) 09:07, 7 July 2022 (UTC)
replies: text: This article is also a kitchen sink...who am I to complain about a few more potato peels in the sink? --Wtshymanski (talk) 00:36, 8 July 2022 (UTC)
thread_title: HCS

message: While trying to find a WP:RS for the 6400 series, I found https://hackaday.com/2021/12/06/ttl-and-cmos-logic-ics-the-building-blocks-of-a-revolution/, which also mentions an 8400 series, which I'd never heard of before.  Don't know any more about it than what I can read on that page, so just mentioning it here to get it recorded somewhere. -- RoySmith (talk) 02:22, 5 March 2023 (UTC)
replies: text: Another data point: A 1970 data sheet from Mullard mentions the 6400 series as equivalent to their FJH xx6 series. Drahtlos (talk) 14:52, 8 March 2023 (UTC)
replies: text: The 6400 series is still alive at Texas Instruments (and has been again since 1989). Drahtlos (talk) 18:44, 6 June 2023 (UTC)
thread_title:  8400? 

message: The family table lists a 74FC family but I can find no reference for it (only the 74FCT family appears to have been manufactured). For the time being I am removing 74FC. Whoever finds a reference, can add it back. Drahtlos (talk) 23:09, 23 March 2023 (UTC)
thread_title:  Family 74FC ? 

message: Hello anonymous editor, the 7400 series includes many IC that are not simple logic IC but counters, ALUs, or drivers. Why would you exclude an SN64BCT125? What about a 74LS125? Or would you exclude the entire 74BCT series? Drahtlos (talk) 20:44, 8 October 2023 (UTC)
thread_title:  Those are not logic circuits per se