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I'm looking for an integrated AND gate with one inverted input that fulfills

\$Y={\overline{A} \cdot B}\$

AND with one inverting input

I know that I could invert one input with a common emitter configuration, however I prefer to implement this gate with as little passives and discretes as possible.

schematic

simulate this circuit – Schematic created using CircuitLab

TonyM
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try-catch-finally
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    you can use a mux – jsotola Sep 14 '21 at 19:47
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    You can build this up from a single chip, the quad 2-input NAND gate. For example the MC74HC00. You just have to connect outputs of some gates to inputs of others. Both NAND and NOR are logically complete (can be used to synthesize any arbitrary logic function). If this interests you let me know and I will write an answer along those lines (or someone else can... OK with me). – user57037 Sep 14 '21 at 19:52
  • mkeith, I know. Until finding SN74LVC1G97 synthesizing this gate with multiple NAND was my last resort anyway. I might just add this to my question. I would add another wiki answer just for completeness, if you do not insist making your own answer. :) – try-catch-finally Sep 14 '21 at 20:07
  • OK. Can't do it now. If nobody else does it before me I will add it to the wiki later (in about 6 or 8 hours). Unless I forget altogether. – user57037 Sep 14 '21 at 20:26
  • If you use differential ECL logic, you can invert one input just by swapping the true and complementary inputs. – The Photon Sep 14 '21 at 22:55
  • Simon Fitch's two nor gate solution is better than my three nand gate solution. – user57037 Sep 15 '21 at 00:16

3 Answers3

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Given that \$ \overline{A} \cdot B = \overline{A + \overline{B}}\$, you can get two of these out of a single 74'02:

enter image description here

Or the same thing, but with the inverter implemented slightly differently (slightly faster, with less input capacitance at B):

enter image description here

Simon Fitch
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13

If Schmitt-Trigger inputs are not an issue there's the configurable multiple-function gate SN74LVC1G97 (and also 1G58 and 1G98 according to page 75 of this) that is wired in a way that allows for using it as various logic gates by combining its inputs selectively.

See the functional modes starting on page 9:

AND with one inverting input from combined logic with SN74LVC1G97

You can use the 1T58 (page 28 of the 2007 Texas Instruments Digital Logic Pocket Data Book) configured with its input "A" set to low, and its inputs "B" and "C" connected to your two inputs A and B. (The inverted input is your A or its "B".)

1T58

JRN
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try-catch-finally
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    On Semi also has similar parts (acquired from buying Fairchild Semi). See NC7SZ57 and NC7SZ58 devices. The OnSemi line has several different parts (with the middle 2 alpha letters different) that operate at different voltage and speed ranges. These can be had in very small USON6 packages or larger SOT23-6/SOT25-6 packages. – BrianB Sep 14 '21 at 19:34
  • Everyone is invited to edit this answer to mention alternative parts (i.e. other manufacturers or multiple multi-function gates in one package) as well. – try-catch-finally Sep 14 '21 at 20:17
  • I realize that the 1T58 I posted is similar to the 1G58 previously mentioned, but I'm thinking maybe the additional image would be helpful. – JRN Sep 15 '21 at 08:02
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Since you proposed a Common Emitter Config with a Pull-up, I conclude that you don't need ultimate speed. In this case, the below circuit might just be enough, although it is neither fast nor very efficient, but uses "no" logic gate and realizes \$Y=A \wedge \overline{B}\$. I would argue that R1 is optional, in case A is short-circuit proof. It is only present to limit current draw from A, when both A and B are high.

schematic

simulate this circuit – Schematic created using CircuitLab

TonyM
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tobalt
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