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I am currently having difficulty locating the circuit diagrams/schematics for the Advanced Schottky versions of the 7400 IC series. While the standard TTL data books seem to have depictions of the L,LS,H, ect, the volumes dealing with both ALS and AS do not seem to contain circuit diagrams.

As http://www.slideshare.net/Ajlaaa/logic-families-16246507 seems to have a diagram for the NAND gate (SN74AS00) (unfortunately does not contain a reference) there should presumably be the others published somewhere.

Does anyone have any idea where these might be published so I can get a look at them?

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    \$\begingroup\$ What do you think you need these for? Even the circuit diagrams that are published are often just simplifications. In any case, it doesn't matter how exactly the chip accomplishes what it does inside. What matters are the specs in the datasheet. \$\endgroup\$
    – Olin Lathrop
    Commented Jun 14, 2015 at 13:44
  • \$\begingroup\$ I want to simulate the chips using LTSpice to see if they would work asynchronously without causing significant problems (ie voltage spikes on changes, ect.) Even though they are simplifications it is nice to be a bit more sure that they will work as intended \$\endgroup\$
    – David Turner
    Commented Jun 14, 2015 at 13:48
  • \$\begingroup\$ No company would publish their actual circuitry because at the very least it would give their competitors access to their intellectual property for free. As Olin says, they are simplifications, which may or may not work as a whole. I've looked through an old TI databook and there is not much there beyond what has been posted. \$\endgroup\$
    – StainlessSteelRat
    Commented Jun 14, 2015 at 20:15
  • \$\begingroup\$ So the answer is that the specific circuits being referenced were, in the vast majority not published, unlike the previous series? I had hoped this would not be the case (though the couple of data books I looked through seemed to suggest it would be). My purpose in asking was to know if there were circuit diagrams in manuals I had overlooked or had not had access to, as apparently by Lorenzo's answer there were. \$\endgroup\$
    – David Turner
    Commented Jun 15, 2015 at 14:26
  • \$\begingroup\$ "to see if they would work asynchronously without causing significant problems" You will have to test physical chips, and you'll have to test every single one of the ones you intend on using - the very ones you intend to put into your boards. Since you're not depending on any specs, testing/qualification of every chip that you use is a must. \$\endgroup\$
    – Kuba hasn't forgotten Monica
    Commented Jun 15, 2015 at 19:45

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I don't know if this TexasInstruments application note would fit your bill, but it contains some schematics and reference for AS logic, like these excerpts:

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Another possibly useful resource is this older application note on AS and ALS logic.

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  • \$\begingroup\$ Very good reading, but it unfortunately only gives the circuit from the 74AS04 (not the ~50 others). It does help prove the point that there is little purpose in testing these against the earlier families, though, as they can be seen to be very different (ti.com/lit/ds/symlink/sn74s04.pdf). Thank You anyway, though. \$\endgroup\$
    – David Turner
    Commented Jun 14, 2015 at 14:21
  • \$\begingroup\$ The older application AS ALS note was interesting too. Contained depiction of 74as00, which will be useful. Unfortunately, it appears the input and output transition models probably won't be enough to model the entire subset of the series that is needed (and, or, nor, nand, xor, xnor, d-latch, mux, demux, ect). Extra information is always appreciated though. \$\endgroup\$
    – David Turner
    Commented Jun 14, 2015 at 14:32
  • \$\begingroup\$ I doubt that even for the 74AS04 this would give you enough information to do any reasonably sane modeling in LTspice. For example, you have almost zero information about the actual transistor implementation on the silicon, and without that, you cannot produce a model which is usable to test the actual speed/delay, for example. Not to speak about the variance of the parameters depending on the temperature... You could in theory ask the manufacturer for a SPICE-model, but it's very unlikely that they have one for such old designs... \$\endgroup\$
    – Laszlo Valko
    Commented Jun 14, 2015 at 15:26
  • \$\begingroup\$ The speed/delay is irrelevant. What I require is seeing if there are any voltage spikes which could propagate in the asynchronous circuit (I'm attempting a home-brew cpu thing out of interest). I am unsure about whether the values of the transistors would influence this, if they do is there any way to estimate, or just enumerate through different possibilities? \$\endgroup\$
    – David Turner
    Commented Jun 14, 2015 at 15:38
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    \$\begingroup\$ @David: voltage spikes come from capacitive & inductive components. Here, in this case, there are no inductors in the circuit by design, only parasytical inductances come into play. Now that's rather difficult to know beforehand, especially since the biggest contributor is the PCB itself. \$\endgroup\$
    – Laszlo Valko
    Commented Jun 14, 2015 at 19:48

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