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How about some citations? Cbdorsett 14:25, 14 November 2006 (UTC)
Here is a link to the text covering tunnel diodes, RCA Tunnel Diode Manual — Preceding unsigned comment added by 118.209.11.103 ( talk) 09:58, 9 January 2020 (UTC)
Diode logic gates were introduced in 50's; I met them for the first time in the late 60's when I went to technical school. I remember I understood the explicit diode OR gate but I was in a maze by this so odd, exotic and absurd diode AND gate... I asked myself many questions as: "Why the diodes were back to front? Why the resistor was connected to +V instead to ground? Why there was no input current when the input voltage was high? And why there was input current when the input voltage was low? But why the current went out of the diodes and went in the input source? What was this absurd? Why it was impossible to make inverting diode gate? Why AND gate was supplied by an additional voltage source while OR gate had not such a source?...and so on...and so on...
It is interesting fact that many years later I continued to not understand what the basic idea behind diode AND was. I perfectly knew the circuit but I didn't understand it... I "saw the trees but I didn't see the forest for them"... And what is more interesting I didn't see any reasonable explanations of this humble circuit somewhere to answer my childhood questions... instead I was seeing thousands of "not seeing the forest" explanations...three months ago), during the laboratory exercises with my students on Digital circuits, I began realizing the great idea behind these legendary diode circuits. I was amazed how simple it was. I shared and considered my insights with these young people and they approved of them; they admired this "elegant simplicity". We decided to share the truth about diode AND gates with wikipedians and Wikipedia readers. That is why, I have written these explanations in the article. In addition, I have listed (in bold) and explained (in italic) below the key points of understanding diode AND gates extracted from the main article.
Is it an original research? I have already explained it in the article about Miller theorem. Yes, it is... but in the common sense of this term, not in the specific Wikipedia OR sense. Really, I have exposed my insights about this circuit solution but I have managed to reduce them to extremely clear, evident and simple explanations that should not be treated as original research in the Wikipedia OR sense; they do not need to be referenced. If you do not agree with me, please insert your comments below the items. Circuit dreamer ( talk, contribs, email) 18:10, 15 January 2011 (UTC)
Circuit dreamer ( talk, contribs, email) 18:10, 15 January 2011 (UTC)
Wtshymanski, I know how to answer in detail to your provocative action but I will not do it since persons as you deserve no such attention; it would be dead loss of time for me. I will only remember to you that the first prerequisite to do something different than cosmetic edit here, in electronics area of Wikipedia, is to have some elementary notion about circuit ideas. But you obviously have no any idea about circuits since if there was even the smallest glimmer of circuit thought in your mind, you would comment the comprehensive explanations above written especially for you and your likes. Circuit dreamer ( talk, contribs, email) 11:59, 16 January 2011 (UTC)
I have a question and a few comments.
1. When was DL invented? Is there a specific date?
2. "output logical 1" and similar expressions in the descriptions of OR and AND operations are repetitive. Stating what 0 and 1 mean once is sufficient.
3. "Powerful diode OR circuits are used in the simple UPS to switch between the main and the standby supply sources." I believe it should sound more like "Powerful diode OR circuits are used in simple UPSs to switch between the mains and the standby supply sources."
ICE77 ( talk) 22:01, 16 February 2011 (UTC)
With respect to the name "Mickey Mouse logic", whose addition Wtshymanski ( talk · contribs) reverted, the person from whom I first heard the term told me it came from some CMOS cookbook or TTL cookbook by Don Lancaster. -- Damian Yerrick ( talk | stalk) 16:53, 26 September 2011 (UTC)
I apologize for the length of this addition to the main article. When I first saw the article on Diode Logic I felt it needed a simpler, more conventional explanation. The original article seemed a bit more "philosophical" than a young mind might find useful. I was encouraged (maybe that is too strong) to write it. About two paragraphs should do it. Then I considered who might read it. I found my way here out of curiosity, what could be said about such a simple circuit. On August 5, 1957 just out of the army and as an electronics technician never having heard of logic circuits I was told to redraw some block diagrams for a design. When I saw blocks labeled AI, OI, -AI and –OI I asked what they were. The engineer sketched a rough schematic of a Diode AND Invert circuit. Its operation was immediately obvious. If the NAND circuit is so simple who would be interested in this article. I concluded the most interested might be someone with no knowledge of logic circuits and possibly very little knowledge of basic electronics. This is not the place to start from basic electronics but I hope by at least explaining the diode someone with very little electronics knowledge might understand this basic function. I hope I achieved my goal. If my contribution is determined to be less than appropriate it can always be deleted. I hope it isn’t. I wish I could have read it when I was eleven years old and in sixth grade. Incidentally one year after that first introduction to the NAND Gate I started designing whole logic families of them. I would still be a technician for another year but I was doing a Junior Engineer's job. Thingmaker ( talk) 19:26, 12 August 2014 (UTC)
This message is primarily for User:Spinningspark but other opinions are welcome.
For the most part I do not feel I am an expert on naming conventions and to a reasonable extent that applies to naming logic circuit families. I spent three years primarily designing CML, DTL, and RTL circuits and related functions. I spent my first eleven years designing transistor circuits of some form or another. Texas Instruments TTL circuits were the first time I heard any of the above naming conventions. Because of this I proclaim not to be an expert and will yield to your judgment.
That said I offer these thoughts: If DL is DRL then shouldn’t DTL be DRTL and TTL be TRTL and maybe RTL be RRTL. Should a simple inverter be RTL since it has resistors and a transistor? Would this make the other RTL less meaningful? It was always my impression that the first letter, D, T, R signified the component that performed the logic. The final T indicated the type of amplifier or inverter. I always assumed the R’s used for biasing were omitted because they were omnipresent in nearly all bi-polar transistor circuits and nearly all other circuits except CMOS type logic. In support of your definition is the transistor logic used in the Apollo Guidance Computer. That circuit has been called RTL which has always bothered me. It is in fact simply an inverter Dot OR logic where the logic takes place by multiple transistors sharing one load resistor. I would call that TL or possibly TTL (I am not trying to teach you just offering thoughts.)
Could there be a standard that explains and defines the rules? Thingmaker ( talk) 14:22, 19 August 2014 (UTC)
It should be noted that this article has been significantly changed as of August 20, 2014. The purpose is to correct the theory that a diode is a switch to the p-n diode theory that a diode is a passive nonlinear impedance with a low impedance and low voltage in the forward direction and a very high impedance in the reverse. Thingmaker ( talk) 14:10, 20 August 2014 (UTC)
I have removed the following passage from the page:
References
I intitially marked this with {{ cn}} and on the claim in quotes {{ cite quote}} but both templates were removed without providing the necessary citations. I think the passage is problematic so am bringing it here for discussion. I realise that the article is almost entirely devoid of references but it can largely be found in numerous textbooks so I am not so concerned with the general lack of references. On the other hand, anecdotes of this sort definitely need sourcing. The rest of the section remaining in the article really needs sourcing as well.
The claim to be the "world's largest transistorized computer" in particular needs a source. I also asked for the quote to be attributed. However, the latest version would seem to indicate that this is not a quote but is WP:SCAREQUOTES and it is not really the largest. Starting off by saying this was the first transistorized computer kind of makes it meaningless anyhow. It would also have been the world's smallest transistorized computer. It is really not appropriate to have this in the article at all as far as I can see. It is also inappropriate to cite this to "the author of this article". Firstly, because anecdote is not a reliable source, but also because it is WP:OWN and self-referential. Spinning Spark 22:52, 21 August 2014 (UTC)
"But why do we need to pull down to -6 volts?" says our hypothetical bright 12-year-old reader, "Doesn't that make the output of the gate -6 V for logic 0, not 0 V ? " And if we have ideal diodes anyway, we don't need the pull-down to a negative voltage. Once we explain the topology of the ideal gates, then we can get to the ugly reality of non-ideal devices with finite switching speed and leakage current, capacitance, minority carrier storage, resistance (of the lossy variety, forsooth) and so forth. A description of how these non-idealities militate against use of diode logic in complex systems would be quite encyclopedia worthy. -- Wtshymanski ( talk) 02:11, 24 August 2014 (UTC)
The text for RD had been changed to RD. This refers to the RD in the schematics. I know of no convention that tells a circuit designer how to name his components other than the obvious such as R, C, L, Q and T. When I created the schematics for the AND and OR circuits I initially used Rd but found that the d was not legible when the image was shrunk. A subscript would be even less legible. Because of this I chose RD. I plan to revert to RD. If this is in violation of a Wikipedia convention then I will change and upload new schematics probably using simply R. This will leave clutter in Wiki Commons but I guess that would be better than using a wrong convention. Whoever says it should be RD can change the text or tell me to and I will fix the schematics. To keep it sensible they should both be changed at the same time. Thingmaker ( talk) 19:22, 24 August 2014 (UTC)
A negative logic AND is not a NOT AND - it's an OR (with negative logic levels). The logic function produced by a set of diodes with common anodes depends on how you assign logic 1 and 0 to voltage levels. Getting a NOT AND without changing the representations of 1 and 0 requires an inverter, which we don't have in pure diode logic. I suppose there could well be circuits where we use positive logic definitions for the first column of diodes, switch to negative logic definitions for the second column, and so on...but I don't think I'd care to present an example. -- Wtshymanski ( talk) 20:50, 25 August 2014 (UTC)
It would be nice to say something about the speed of diode circuits, and the limitations on speed. And I've just seen a snipped of something on Google Books that describes using tunnel diodes for logic, but it wasn't clear if it was the same sort of topology as we're looking at here...sounded quite fast for its time period, though. -- Wtshymanski ( talk) 01:02, 26 August 2014 (UTC)
Does the 550 switching diodes for the clock in the Diode–transistor logic article prove that the PN diode is a switch? I have the explanation of how a diode switch works. Click on this User talk:Thingmaker#Reference point. The simple PN diode chip puts integrated circuits to shame. Possibly instead of looking for published documentation of “someone” calling the diode a switch one might just read p-n junction or p-n diode and see if they can find how the pn diode is a switch. Thingmaker ( talk) 20:40, 27 August 2014 (UTC)
"2.Jump up ^ The outputs of conventional ICs with complementary output stages may be connected together if they always are at the same voltages." If they are always at the same voltage levels why would it be necessary to connect them together? Either one would provide the same signal. It is never wise to connect complementary outputs together. Even a transient difference would be harmful. If they are not "always" the same then they better not be connected together. Shouldn't this be removed? Thingmaker ( talk) 19:04, 3 September 2014 (UTC)
Has anyone seen the recent work to create inverting diode logic by using an RF power supply component? [1]
Notes on this: The logic circuits themselves are diodes with passives (resistors, capacitors and inductors). The circuits the person has created have an RF power supply that is built around a 74AC14 (Hex Schmitt inverter), but it's limited to the RF power supply. It should be possible to make such power supplies without the use of IC's, and possibly even without the use of transistors. May only be worth mentioning in the context that while inverting diode logic is apparently possible, it requires a lot more circuitry and an RF supply. Cefiar ( talk) 03:14, 30 May 2016 (UTC)
I am tempted to change the first paragraph into two, with the following content:
In logic gates, logical functions are performed by parallel or series connected switches (such as relay contacts or insulated gate FETs like CMOS) controlled by logical inputs or parallel resistors or diodes which are passive components. Diode logic is implemented by diodes which exhibit low impedance when forward biased and a very high impedance when reverse biased.
There are mainly two kinds of diode logic gates - OR and AND. While it is possible to construct an inverting logic diode gate [2], it is fairly impractical and requires a large amount of extra circuitry apart from diodes and resistors (capacitors, inductors and an RF supply). The only other way to create a NOT or Invert function requires an active component such as a transistor. As such, this article will concentrate on basic diode logic.
Any objections? Ping Thingmaker & SpinningSpark. Feel free to make the change yourselves or rework the above to suit. Cefiar ( talk) 05:32, 21 June 2016 (UTC)
References
@ Kvng: Why did you remove the note about handmade transistors as unsuppoted? This book says that making handmade transistors ended in 1952, which means they were likely not used in the IBM 608 and the note was probably correct that they were used in the IBM 360 and 370 (and since that is the subject of the book, makes it even more likely). That has now left the article saying something almost certainly not true. Spinning Spark 19:03, 17 August 2019 (UTC)
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How about some citations? Cbdorsett 14:25, 14 November 2006 (UTC)
Here is a link to the text covering tunnel diodes, RCA Tunnel Diode Manual — Preceding unsigned comment added by 118.209.11.103 ( talk) 09:58, 9 January 2020 (UTC)
Diode logic gates were introduced in 50's; I met them for the first time in the late 60's when I went to technical school. I remember I understood the explicit diode OR gate but I was in a maze by this so odd, exotic and absurd diode AND gate... I asked myself many questions as: "Why the diodes were back to front? Why the resistor was connected to +V instead to ground? Why there was no input current when the input voltage was high? And why there was input current when the input voltage was low? But why the current went out of the diodes and went in the input source? What was this absurd? Why it was impossible to make inverting diode gate? Why AND gate was supplied by an additional voltage source while OR gate had not such a source?...and so on...and so on...
It is interesting fact that many years later I continued to not understand what the basic idea behind diode AND was. I perfectly knew the circuit but I didn't understand it... I "saw the trees but I didn't see the forest for them"... And what is more interesting I didn't see any reasonable explanations of this humble circuit somewhere to answer my childhood questions... instead I was seeing thousands of "not seeing the forest" explanations...three months ago), during the laboratory exercises with my students on Digital circuits, I began realizing the great idea behind these legendary diode circuits. I was amazed how simple it was. I shared and considered my insights with these young people and they approved of them; they admired this "elegant simplicity". We decided to share the truth about diode AND gates with wikipedians and Wikipedia readers. That is why, I have written these explanations in the article. In addition, I have listed (in bold) and explained (in italic) below the key points of understanding diode AND gates extracted from the main article.
Is it an original research? I have already explained it in the article about Miller theorem. Yes, it is... but in the common sense of this term, not in the specific Wikipedia OR sense. Really, I have exposed my insights about this circuit solution but I have managed to reduce them to extremely clear, evident and simple explanations that should not be treated as original research in the Wikipedia OR sense; they do not need to be referenced. If you do not agree with me, please insert your comments below the items. Circuit dreamer ( talk, contribs, email) 18:10, 15 January 2011 (UTC)
Circuit dreamer ( talk, contribs, email) 18:10, 15 January 2011 (UTC)
Wtshymanski, I know how to answer in detail to your provocative action but I will not do it since persons as you deserve no such attention; it would be dead loss of time for me. I will only remember to you that the first prerequisite to do something different than cosmetic edit here, in electronics area of Wikipedia, is to have some elementary notion about circuit ideas. But you obviously have no any idea about circuits since if there was even the smallest glimmer of circuit thought in your mind, you would comment the comprehensive explanations above written especially for you and your likes. Circuit dreamer ( talk, contribs, email) 11:59, 16 January 2011 (UTC)
I have a question and a few comments.
1. When was DL invented? Is there a specific date?
2. "output logical 1" and similar expressions in the descriptions of OR and AND operations are repetitive. Stating what 0 and 1 mean once is sufficient.
3. "Powerful diode OR circuits are used in the simple UPS to switch between the main and the standby supply sources." I believe it should sound more like "Powerful diode OR circuits are used in simple UPSs to switch between the mains and the standby supply sources."
ICE77 ( talk) 22:01, 16 February 2011 (UTC)
With respect to the name "Mickey Mouse logic", whose addition Wtshymanski ( talk · contribs) reverted, the person from whom I first heard the term told me it came from some CMOS cookbook or TTL cookbook by Don Lancaster. -- Damian Yerrick ( talk | stalk) 16:53, 26 September 2011 (UTC)
I apologize for the length of this addition to the main article. When I first saw the article on Diode Logic I felt it needed a simpler, more conventional explanation. The original article seemed a bit more "philosophical" than a young mind might find useful. I was encouraged (maybe that is too strong) to write it. About two paragraphs should do it. Then I considered who might read it. I found my way here out of curiosity, what could be said about such a simple circuit. On August 5, 1957 just out of the army and as an electronics technician never having heard of logic circuits I was told to redraw some block diagrams for a design. When I saw blocks labeled AI, OI, -AI and –OI I asked what they were. The engineer sketched a rough schematic of a Diode AND Invert circuit. Its operation was immediately obvious. If the NAND circuit is so simple who would be interested in this article. I concluded the most interested might be someone with no knowledge of logic circuits and possibly very little knowledge of basic electronics. This is not the place to start from basic electronics but I hope by at least explaining the diode someone with very little electronics knowledge might understand this basic function. I hope I achieved my goal. If my contribution is determined to be less than appropriate it can always be deleted. I hope it isn’t. I wish I could have read it when I was eleven years old and in sixth grade. Incidentally one year after that first introduction to the NAND Gate I started designing whole logic families of them. I would still be a technician for another year but I was doing a Junior Engineer's job. Thingmaker ( talk) 19:26, 12 August 2014 (UTC)
This message is primarily for User:Spinningspark but other opinions are welcome.
For the most part I do not feel I am an expert on naming conventions and to a reasonable extent that applies to naming logic circuit families. I spent three years primarily designing CML, DTL, and RTL circuits and related functions. I spent my first eleven years designing transistor circuits of some form or another. Texas Instruments TTL circuits were the first time I heard any of the above naming conventions. Because of this I proclaim not to be an expert and will yield to your judgment.
That said I offer these thoughts: If DL is DRL then shouldn’t DTL be DRTL and TTL be TRTL and maybe RTL be RRTL. Should a simple inverter be RTL since it has resistors and a transistor? Would this make the other RTL less meaningful? It was always my impression that the first letter, D, T, R signified the component that performed the logic. The final T indicated the type of amplifier or inverter. I always assumed the R’s used for biasing were omitted because they were omnipresent in nearly all bi-polar transistor circuits and nearly all other circuits except CMOS type logic. In support of your definition is the transistor logic used in the Apollo Guidance Computer. That circuit has been called RTL which has always bothered me. It is in fact simply an inverter Dot OR logic where the logic takes place by multiple transistors sharing one load resistor. I would call that TL or possibly TTL (I am not trying to teach you just offering thoughts.)
Could there be a standard that explains and defines the rules? Thingmaker ( talk) 14:22, 19 August 2014 (UTC)
It should be noted that this article has been significantly changed as of August 20, 2014. The purpose is to correct the theory that a diode is a switch to the p-n diode theory that a diode is a passive nonlinear impedance with a low impedance and low voltage in the forward direction and a very high impedance in the reverse. Thingmaker ( talk) 14:10, 20 August 2014 (UTC)
I have removed the following passage from the page:
References
I intitially marked this with {{ cn}} and on the claim in quotes {{ cite quote}} but both templates were removed without providing the necessary citations. I think the passage is problematic so am bringing it here for discussion. I realise that the article is almost entirely devoid of references but it can largely be found in numerous textbooks so I am not so concerned with the general lack of references. On the other hand, anecdotes of this sort definitely need sourcing. The rest of the section remaining in the article really needs sourcing as well.
The claim to be the "world's largest transistorized computer" in particular needs a source. I also asked for the quote to be attributed. However, the latest version would seem to indicate that this is not a quote but is WP:SCAREQUOTES and it is not really the largest. Starting off by saying this was the first transistorized computer kind of makes it meaningless anyhow. It would also have been the world's smallest transistorized computer. It is really not appropriate to have this in the article at all as far as I can see. It is also inappropriate to cite this to "the author of this article". Firstly, because anecdote is not a reliable source, but also because it is WP:OWN and self-referential. Spinning Spark 22:52, 21 August 2014 (UTC)
"But why do we need to pull down to -6 volts?" says our hypothetical bright 12-year-old reader, "Doesn't that make the output of the gate -6 V for logic 0, not 0 V ? " And if we have ideal diodes anyway, we don't need the pull-down to a negative voltage. Once we explain the topology of the ideal gates, then we can get to the ugly reality of non-ideal devices with finite switching speed and leakage current, capacitance, minority carrier storage, resistance (of the lossy variety, forsooth) and so forth. A description of how these non-idealities militate against use of diode logic in complex systems would be quite encyclopedia worthy. -- Wtshymanski ( talk) 02:11, 24 August 2014 (UTC)
The text for RD had been changed to RD. This refers to the RD in the schematics. I know of no convention that tells a circuit designer how to name his components other than the obvious such as R, C, L, Q and T. When I created the schematics for the AND and OR circuits I initially used Rd but found that the d was not legible when the image was shrunk. A subscript would be even less legible. Because of this I chose RD. I plan to revert to RD. If this is in violation of a Wikipedia convention then I will change and upload new schematics probably using simply R. This will leave clutter in Wiki Commons but I guess that would be better than using a wrong convention. Whoever says it should be RD can change the text or tell me to and I will fix the schematics. To keep it sensible they should both be changed at the same time. Thingmaker ( talk) 19:22, 24 August 2014 (UTC)
A negative logic AND is not a NOT AND - it's an OR (with negative logic levels). The logic function produced by a set of diodes with common anodes depends on how you assign logic 1 and 0 to voltage levels. Getting a NOT AND without changing the representations of 1 and 0 requires an inverter, which we don't have in pure diode logic. I suppose there could well be circuits where we use positive logic definitions for the first column of diodes, switch to negative logic definitions for the second column, and so on...but I don't think I'd care to present an example. -- Wtshymanski ( talk) 20:50, 25 August 2014 (UTC)
It would be nice to say something about the speed of diode circuits, and the limitations on speed. And I've just seen a snipped of something on Google Books that describes using tunnel diodes for logic, but it wasn't clear if it was the same sort of topology as we're looking at here...sounded quite fast for its time period, though. -- Wtshymanski ( talk) 01:02, 26 August 2014 (UTC)
Does the 550 switching diodes for the clock in the Diode–transistor logic article prove that the PN diode is a switch? I have the explanation of how a diode switch works. Click on this User talk:Thingmaker#Reference point. The simple PN diode chip puts integrated circuits to shame. Possibly instead of looking for published documentation of “someone” calling the diode a switch one might just read p-n junction or p-n diode and see if they can find how the pn diode is a switch. Thingmaker ( talk) 20:40, 27 August 2014 (UTC)
"2.Jump up ^ The outputs of conventional ICs with complementary output stages may be connected together if they always are at the same voltages." If they are always at the same voltage levels why would it be necessary to connect them together? Either one would provide the same signal. It is never wise to connect complementary outputs together. Even a transient difference would be harmful. If they are not "always" the same then they better not be connected together. Shouldn't this be removed? Thingmaker ( talk) 19:04, 3 September 2014 (UTC)
Has anyone seen the recent work to create inverting diode logic by using an RF power supply component? [1]
Notes on this: The logic circuits themselves are diodes with passives (resistors, capacitors and inductors). The circuits the person has created have an RF power supply that is built around a 74AC14 (Hex Schmitt inverter), but it's limited to the RF power supply. It should be possible to make such power supplies without the use of IC's, and possibly even without the use of transistors. May only be worth mentioning in the context that while inverting diode logic is apparently possible, it requires a lot more circuitry and an RF supply. Cefiar ( talk) 03:14, 30 May 2016 (UTC)
I am tempted to change the first paragraph into two, with the following content:
In logic gates, logical functions are performed by parallel or series connected switches (such as relay contacts or insulated gate FETs like CMOS) controlled by logical inputs or parallel resistors or diodes which are passive components. Diode logic is implemented by diodes which exhibit low impedance when forward biased and a very high impedance when reverse biased.
There are mainly two kinds of diode logic gates - OR and AND. While it is possible to construct an inverting logic diode gate [2], it is fairly impractical and requires a large amount of extra circuitry apart from diodes and resistors (capacitors, inductors and an RF supply). The only other way to create a NOT or Invert function requires an active component such as a transistor. As such, this article will concentrate on basic diode logic.
Any objections? Ping Thingmaker & SpinningSpark. Feel free to make the change yourselves or rework the above to suit. Cefiar ( talk) 05:32, 21 June 2016 (UTC)
References
@ Kvng: Why did you remove the note about handmade transistors as unsuppoted? This book says that making handmade transistors ended in 1952, which means they were likely not used in the IBM 608 and the note was probably correct that they were used in the IBM 360 and 370 (and since that is the subject of the book, makes it even more likely). That has now left the article saying something almost certainly not true. Spinning Spark 19:03, 17 August 2019 (UTC)