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F and AS plus G

The article at the page http://en.wikipedia.org/Logic_family says that F and AS came out in 1979 and 1980, not in 1985 like in this article. Something needs to be changed and corrected. The G family from 2004 is not mentioned in this article.

I fixed the "Sub-types" section by moving out of the dotted list the last three sentences since they really weren't in the right place.

ICE77 (talk) 23:16, 19 February 2011 (UTC)

Schematic diagram question

Why is not in fig "Two-input TTL NAND gate" a bias resistor for the base of output transistor? — Preceding unsigned comment added by Oabernhardt (talk • contribs) 14:49, 11 June 2012 (UTC)

For one thing, it's a simplified diagram. For another, current will flow from V_cc through the resistor to the base of the input transistor, then through the base-collector junction to the base of the output transistor. Jc3s5h (talk) 16:08, 11 June 2012 (UTC)

Yes, it is an oversimplified diagram. The output transistor will either get is base drive from the resistor through the multiple emitter transistor's B-C junction, or the collector of the of ME transistor will suck out the base charge. If you consider the threshold voltage in the simple diagram, it is around 0.7V -- not the 1.4V of a typical TTL gate. The totem pole circuit lower down is better for details. Glrx (talk) 17:13, 11 June 2012 (UTC)

Sub-types

There seems to be a lot of overlap between the Transistor–transistor logic#Sub-types section and the 7400 series#7400 series derivative families section.

Could we merge that information together somehow?

Are there any Fast (F) or Advanced-Schottky (AS) chips other than the ones in the 7400 series -- the 74F and 74AS, respectively?

--DavidCary (talk) 14:18, 16 October 2014 (UTC)

Pin counts

"Like most integrated circuits of the period 1965–1990, TTL devices are usually packaged in through-hole, dual in-line packages with between 14 and 24 lead wires" this seems a strange and unsupported claim. Most of what I have on hand is 6 or 8 pin. Original research, but why would there be a good cite that would have average pin counts that would support the claim? It seems very dubious. Obviously in certain applications it would be true, but how would it be true generally for TTL devices? Any TTL device with 14 or more pins is going to contain a large number of components, and those smaller components are probably all available for order as discrete units with less pins, and still in PDIP. 76.105.216.34 (talk) 23:48, 21 January 2015 (UTC)

I would have trouble remembering much about TTL, but I do not think I've ever seen 6 or 8 pin TTL chips. What are they? Can you link to a description somewhere (no problem if you can't; just my curiosity). Have a look at 7400 series to see confirmation of the statement in the article. By modern standards, there are hardly any components at all in a 7400, yet it has 14 pins simply because it has to, per the diagram in the lead. Johnuniq (talk) 05:55, 22 January 2015 (UTC)

I agree. Most TTL parts were 14 or 16 pins; a few were 20 or more. What comes with fewer than 14? Is a 555 timer considered TTL? I don't think so. Dicklyon (talk) 06:56, 22 January 2015 (UTC)

Easily verified: simply go to List of 7400 series integrated circuits, pick a few at random, look at the data sheet and count the pins. Mostly 14 and 16, occasionally 20. Of course there is the 741G series, for those times when you have to cram one more gate into an overcrowded surface-mount board, but those are modern HC parts. There was nothing like that in the days when TTL was king. --Guy Macon (talk) 11:56, 22 January 2015 (UTC)

You're right, but you're not Misplaced Pages right. We can't use Misplaced Pages as a source to settle arguments on Misplaced Pages. We can't flip through data books and count how many parts have how many pins - that's WP:OR. What we Wikishould do is tag the offending line with "Citation needed", which will stay on it till the end of time waiting for someone to find a reliable third party secondary source making the statement. --Wtshymanski (talk) 23:00, 23 January 2015 (UTC)

I have seldom met a data sheet that does not specify the number of pins a part has, so counting them is completely unnecessary. Since the data sheet itself is the cite for the pin count, you are just talking bollocks. 31.48.73.38 (talk) 17:34, 24 January 2015 (UTC)

Wtshymanski, who disagrees with certain Misplaced Pages policies, in this case pretty much accurately describes the policies in question. If someone seriously questions that claim "TTL devices are usually packaged in through-hole, dual in-line packages with between 14 and 24 lead wires", then we as an encyclopedia must back up the claim with a citation to a reliable source.

In my comment above, I was inexact in my language. Checking a bunch of datasheets should be enough to convince any reasonable person how many pins TTL devices "usually" have, but Wtshymanski is entirely correct when he says that that doing that violates our policy on original research. It's actually a pretty good example illustrating why Wtshymanski disagrees with those Misplaced Pages policies.

My personal view is that, while Wtshymanski has a point about our policies being flawed, his proposed alternative (as far as I can tell -- he hasn't really detailed exactly how he thinks Misplaced Pages should change, but I think he wants it to be more like Nupedia) is worse. I would love to have a serious discussion about this -- or about anything else, for that matter -- with Wtshymanski, but he has shown no interest in doing that. --Guy Macon (talk) 16:42, 25 January 2015 (UTC)

@Guy Macon:If I read you right: then what you are both saying is that if anyone puts a claim in a Misplaced Pages article, having found a book, website or whatever that supports the claim and cites the reference in the article (as millions of such claims are cited), then all such claims can be deleted as OR|original research because the act of looking the claim up in the book is original research?? I have to disagree here. I accept that if I emptied out my box of 7400 series chips and counted the pins that would be original research (which is what Wtshymanski was suggesting). I cannot accept that citing the data sheets that specify the number of pins on the chips to be original research.

Alternatively, of course, I could photograph the chips with numbered stickers on each pin and include that because original research is allowed in images. 31.48.73.38 (talk) 13:35, 26 January 2015 (UTC)

No. You have an incorrect grasp of Misplaced Pages's rules on original research. Citing a source is not original research. You might find WP:SYNTH helpful in understanding the policy. --Guy Macon (talk) 23:02, 26 January 2015 (UTC)

@Guy Macon: Which bit of, "I cannot accept that citing the data sheets that specify the number of pins on the chips to be original research" is any different to, "Citing a source is not original research". I am merely provided a précis of what you posted. 31.48.73.38 (talk) 17:30, 1 February 2015 (UTC)

Let's just cite a book. How about this one that says "these devices are usually encapsulated in a plastic 14-pin, 16-pin, or 24-pin dual-in-line package (DIP)" (referring to 7400 series TTL in particular). Dicklyon (talk) 17:52, 25 January 2015 (UTC)

My character plays Lancaster, Don (1974). "1". TTL Cookbook. Howard W. Sams and Co., Inc The Bobbs-Merril Co., Inc. p. 14. ISBN 0-672-21035-5. The majority of devices are available in the common 14-pin and 16-pin DIP or dual in-line package... {{cite book}}: Check |author-link1= value (help); Cite has empty unknown parameters: |doi_brokendate=, |separator=, and |nopp= (help) and walks off in a cloud of Wikismugness, showing his superiority by proving a reference for the bloody obvious exists. Suggested ripostes includeWP:OUTDATED,WP:SPS, WP:QS, WP:1R and I'm sure there's a whole bunch of procedurally sound objections based on more than 14 years of carefully planned policies and sacred consensus. And 40 pins is not 49 pins. --Wtshymanski (talk) 18:07, 25 January 2015 (UTC)

What the hell are you smoking? 31.48.73.38 (talk) 17:30, 1 February 2015 (UTC)

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