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The article at the page http://en.wikipedia.org/wiki/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)
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)
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)
Seems to me that the HC and HCT are not subtypes of TTL. The use the numbering system of TTL, but otherwise are somewhat different. The important idea behind TTL, successor of RTL and DTL, is using bipolar transistors for both logic and output drivers. The logic transistors can go into reverse active mode and such charge out of the following transistor, speeding up the logic. Now, many S and LS circuits use Schottky diodes for logic functions, so aren't strictly TTL, but otherwise are similar enough. Not that HC and HCT should be ignored, but they aren't subtypes of TTL. Gah4 ( talk) 23:04, 28 October 2015 (UTC)
"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)
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)
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 include
WP: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)I think sometimes the idea of original research isn't well defined. Seems like a reference to the TTL data book, describing hundreds of TTL chips, should be enough to settle the question. I don't think we need a government funded, peer-reviewed study on the number of pins on a chip to know how many there are. I do agree that there are plenty of cases where original research is a problem, when no sources are available to show the difference, and reliable funded, and reviewed studies are needed. I don't believe that this is one of those. In the case of TTL I suspect (uh-oh, original research) that standardizing on 14 and 16 pin packages helped with the economy of scale, and kept prices down. It also might have made board layout easier when computers were slower. Gah4 ( talk) 23:16, 28 October 2015 (UTC)
Move to change citation method
Style is basically Harvard footnotes.
Harvard expression were inconsistent. See https://en.wikipedia.org/?title=Transistor%E2%80%93transistor_logic&oldid=644140821 Some had year, some didn't. Some gave initials, some didn't. Some used ampersand; some didn't. Some had comma-year; some didn't. The linkage specified material twice:
<ref>[[#CITEErin2003|Eren, H., 2003.]]</ref>
To make it consistent, use the simpler (with a rename of CITEErin2003 to CITERefEren2003) (also note that Eren was mispelled):
<ref>{{harvnb|Eren|2003}}</ref>
That basically takes you to this version (harv templates to existing citation style): https://en.wikipedia.org/?title=Transistor%E2%80%93transistor_logic&oldid=645034423
If you actually look at the references, you'll see
* <cite id=CITEHorowitzHill1989>Horowitz, P. and Winfield Hill, W. ''The Art of Electronics.'' 2nd Ed. Cambridge University Press. 1989. ISBN 0-521-37095-7</cite>
With the doubled single quotes, the intention was to italicize the title but not the authors, but that doesn't happen inside the cite tag. That's when I switched to the citation templates in the reference section. You'll also notice author Hill is confused.
In templating the refs, other errors came out and I added dois.
Glrx ( talk) 17:47, 2 February 2015 (UTC)
ref=harv
(see
Help:Citation Style 1#Anchors), so I usually match Harvard refs with {{
citation}}. That way the sfn anchor is there by default.ref
tags and invoke {{
reflist}} at the bottom of the page; an editor need not edit both inline (sfn/harv) and out-of-line (biblio). I think mouseover works better with long footnotes.Why are the transistors in the diagrams V? Most use Q for transistors. Gah4 ( talk) 00:40, 3 April 2015 (UTC)
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User:117.206.94.11, User:157.49.131.192, and User:Charanreddy1984 have all made substantially the same edit:
This is poor grammar and incorrect wikilinking, as explained by User:Johnuniq at User talk:Charanreddy1984#Transistor-transistor logic. More importantly, it is factually false.
Refer to the diagram in the article with the caption "Two-input TTL NAND gate with a simple output stage (simplified)". There is one multi-emitter transistor toward the left of the diagram, connected to the inputs A & B. There is another transistor, with one emitter, toward the right of the diagram, with one emitter connected to ground. The disputed passage, after the change, purports that ground is an input, because it is connected to an emitter. This is absurd.
The diagram with the caption "Standard TTL NAND with a "totem-pole" output stage, one of four in 7400" shows another TTL circuit, this one has four transistors, only one of which has its emitters connected to inputs. Jc3s5h ( talk) 14:48, 8 February 2018 (UTC)
I have made some initial mods to the Multiple-emitter transistor article. Specifically, I added some cross sections and symbols. Overjive ( talk) 00:13, 11 February 2018 (UTC)
References
There is recent discussion, in edit summary, about how long TTL will last. In 1995, I was at a conference related to FPGAs, with the major vendors there, and started a discussion about the need for affordable FPGA software. (At the time, it cost thousands of dollars.) When I was younger, TTL devices were easily available for building things like clocks, or other fun projects. But I suspected that wouldn't last forever, and that younger digital hardware engineers would need something else to play with, and that might be FPGAs. As far as I know, the reason we now have freely available FPGA software is unrelated to that, and surprise, 24 years later we still have TTL chips to play with. I suspect, though, that eventually most will go away. Simpler gates and high current bus drivers might stay around longer. Gah4 ( talk) 00:32, 15 May 2019 (UTC)
I have looked for switching times of gates. I am aware that they may differ between types of transistors, types of gates, fanout and length of the output wire. However, I would be very pleased to see some information about the delay times between signal changes on inputs of a gate and the change (if any) on the output. Thanks, Jos Jacob.Koot ( talk) 20:51, 15 December 2020 (UTC)
There is no concept of "standard TTL voltage" outside of specific ICs and protocols. However if one were to talk about a "common" TTL voltage, then 3.3V should be mentioned, as the vast majority of ICs made for electronics today can use 3.3V, while only a subset can take 5V. — Preceding unsigned comment added by 130.126.255.83 ( talk) 20:41, 18 October 2021 (UTC)
Push–pull output mentions TTL, but then later notes that it is actually (as we know, and all the data sheets say) totem-pole. As well as I know, a real Push–pull output should be somewhat symmetric, which TTL isn't. Gah4 ( talk) 06:40, 9 November 2022 (UTC) Note also, that I don't believe that it is a requirement that Push–pull output pull below ground. Depending on where you call ground, there are many amplifiers that don't do that. OK, it doesn't actually say push-pull, but the LM380 was many years ago my favorite amplifier. It doesn't pull below ground, but is designed to go half way in quiescent state. Then a capacitor allows for +/- speaker drive. Gah4 ( talk) 06:53, 9 November 2022 (UTC)
This Â
level-5 vital article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||
|
|
||
The article at the page http://en.wikipedia.org/wiki/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)
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)
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)
Seems to me that the HC and HCT are not subtypes of TTL. The use the numbering system of TTL, but otherwise are somewhat different. The important idea behind TTL, successor of RTL and DTL, is using bipolar transistors for both logic and output drivers. The logic transistors can go into reverse active mode and such charge out of the following transistor, speeding up the logic. Now, many S and LS circuits use Schottky diodes for logic functions, so aren't strictly TTL, but otherwise are similar enough. Not that HC and HCT should be ignored, but they aren't subtypes of TTL. Gah4 ( talk) 23:04, 28 October 2015 (UTC)
"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)
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)
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 include
WP: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)I think sometimes the idea of original research isn't well defined. Seems like a reference to the TTL data book, describing hundreds of TTL chips, should be enough to settle the question. I don't think we need a government funded, peer-reviewed study on the number of pins on a chip to know how many there are. I do agree that there are plenty of cases where original research is a problem, when no sources are available to show the difference, and reliable funded, and reviewed studies are needed. I don't believe that this is one of those. In the case of TTL I suspect (uh-oh, original research) that standardizing on 14 and 16 pin packages helped with the economy of scale, and kept prices down. It also might have made board layout easier when computers were slower. Gah4 ( talk) 23:16, 28 October 2015 (UTC)
Move to change citation method
Style is basically Harvard footnotes.
Harvard expression were inconsistent. See https://en.wikipedia.org/?title=Transistor%E2%80%93transistor_logic&oldid=644140821 Some had year, some didn't. Some gave initials, some didn't. Some used ampersand; some didn't. Some had comma-year; some didn't. The linkage specified material twice:
<ref>[[#CITEErin2003|Eren, H., 2003.]]</ref>
To make it consistent, use the simpler (with a rename of CITEErin2003 to CITERefEren2003) (also note that Eren was mispelled):
<ref>{{harvnb|Eren|2003}}</ref>
That basically takes you to this version (harv templates to existing citation style): https://en.wikipedia.org/?title=Transistor%E2%80%93transistor_logic&oldid=645034423
If you actually look at the references, you'll see
* <cite id=CITEHorowitzHill1989>Horowitz, P. and Winfield Hill, W. ''The Art of Electronics.'' 2nd Ed. Cambridge University Press. 1989. ISBN 0-521-37095-7</cite>
With the doubled single quotes, the intention was to italicize the title but not the authors, but that doesn't happen inside the cite tag. That's when I switched to the citation templates in the reference section. You'll also notice author Hill is confused.
In templating the refs, other errors came out and I added dois.
Glrx ( talk) 17:47, 2 February 2015 (UTC)
ref=harv
(see
Help:Citation Style 1#Anchors), so I usually match Harvard refs with {{
citation}}. That way the sfn anchor is there by default.ref
tags and invoke {{
reflist}} at the bottom of the page; an editor need not edit both inline (sfn/harv) and out-of-line (biblio). I think mouseover works better with long footnotes.Why are the transistors in the diagrams V? Most use Q for transistors. Gah4 ( talk) 00:40, 3 April 2015 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Transistor–transistor logic. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
This message was posted before February 2018.
After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than
regular verification using the archive tool instructions below. Editors
have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the
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source check}}
(last update: 5 June 2024).
Cheers.— InternetArchiveBot ( Report bug) 05:35, 23 March 2017 (UTC)
User:117.206.94.11, User:157.49.131.192, and User:Charanreddy1984 have all made substantially the same edit:
This is poor grammar and incorrect wikilinking, as explained by User:Johnuniq at User talk:Charanreddy1984#Transistor-transistor logic. More importantly, it is factually false.
Refer to the diagram in the article with the caption "Two-input TTL NAND gate with a simple output stage (simplified)". There is one multi-emitter transistor toward the left of the diagram, connected to the inputs A & B. There is another transistor, with one emitter, toward the right of the diagram, with one emitter connected to ground. The disputed passage, after the change, purports that ground is an input, because it is connected to an emitter. This is absurd.
The diagram with the caption "Standard TTL NAND with a "totem-pole" output stage, one of four in 7400" shows another TTL circuit, this one has four transistors, only one of which has its emitters connected to inputs. Jc3s5h ( talk) 14:48, 8 February 2018 (UTC)
I have made some initial mods to the Multiple-emitter transistor article. Specifically, I added some cross sections and symbols. Overjive ( talk) 00:13, 11 February 2018 (UTC)
References
There is recent discussion, in edit summary, about how long TTL will last. In 1995, I was at a conference related to FPGAs, with the major vendors there, and started a discussion about the need for affordable FPGA software. (At the time, it cost thousands of dollars.) When I was younger, TTL devices were easily available for building things like clocks, or other fun projects. But I suspected that wouldn't last forever, and that younger digital hardware engineers would need something else to play with, and that might be FPGAs. As far as I know, the reason we now have freely available FPGA software is unrelated to that, and surprise, 24 years later we still have TTL chips to play with. I suspect, though, that eventually most will go away. Simpler gates and high current bus drivers might stay around longer. Gah4 ( talk) 00:32, 15 May 2019 (UTC)
I have looked for switching times of gates. I am aware that they may differ between types of transistors, types of gates, fanout and length of the output wire. However, I would be very pleased to see some information about the delay times between signal changes on inputs of a gate and the change (if any) on the output. Thanks, Jos Jacob.Koot ( talk) 20:51, 15 December 2020 (UTC)
There is no concept of "standard TTL voltage" outside of specific ICs and protocols. However if one were to talk about a "common" TTL voltage, then 3.3V should be mentioned, as the vast majority of ICs made for electronics today can use 3.3V, while only a subset can take 5V. — Preceding unsigned comment added by 130.126.255.83 ( talk) 20:41, 18 October 2021 (UTC)
Push–pull output mentions TTL, but then later notes that it is actually (as we know, and all the data sheets say) totem-pole. As well as I know, a real Push–pull output should be somewhat symmetric, which TTL isn't. Gah4 ( talk) 06:40, 9 November 2022 (UTC) Note also, that I don't believe that it is a requirement that Push–pull output pull below ground. Depending on where you call ground, there are many amplifiers that don't do that. OK, it doesn't actually say push-pull, but the LM380 was many years ago my favorite amplifier. It doesn't pull below ground, but is designed to go half way in quiescent state. Then a capacitor allows for +/- speaker drive. Gah4 ( talk) 06:53, 9 November 2022 (UTC)