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I know I can do this with two separate NAND gates, but it would be more space consuming. Is there a single standard logic gate (e.g.; 74V1Gxxx - SOT-23 package is preferred) which produces this result?

Or, can I get this result by using two transistors at most?

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You should write \$\overline{\overline{A}B} = A + \overline{B}\$ instead of \$\overline{A}B = A + \overline{B}\$. :) –  nidhin May 28 at 11:31
    
Ah, you are right. Fixing it now. –  hkBattousai May 28 at 11:32
    
I think there is no such gate as \$\overline{A}B\$. List of 74XX. –  nidhin May 28 at 11:38

4 Answers 4

up vote 14 down vote accepted

Sure, you could use a 74AXP1G57 "Low-power configurable multiple function gate"

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It comes in a very small 6-pin package.

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2  
'1G57 for the smaller problems, '1G99 for the larger ones (no puns intended). –  Ignacio Vazquez-Abrams May 28 at 12:34
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That's nice, because a dual NAND package would be at least 8 pins. –  Ben Voigt May 28 at 15:53
    
Do I read correctly that there are four ways to hook this up as an OR-NOT (A=0, B=1, A=C, B=C) but no way to use it as an OR, NAND or AND-NOT? –  Jan Dvorak May 29 at 5:08
    
@JanDvorak It's not really a universal gate, but it does some interesting things- most multiple-input gates are symmetric- and the ST inputs are usually an advantage (especially for applications like roll-your-own SMPS designs). –  Spehro Pefhany May 29 at 12:59

You could wire up a SN74LVC2G157 to do this function.

In general, when you need arbitrary logic, think "multiplexer."

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You could wire up an LM556 (dual 555 timer IC), with the input stage wired normally and the output stage wired as an inverter.

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It doesn't really answer the question, but that link ("Is the 555 complete in the Boolean sense") is loaded with an insane amount of awesomeness (or maybe the reverse). –  Spehro Pefhany May 28 at 17:39
    
People do amazing things with 555s. :) –  hoosierEE May 28 at 19:36

I think this would take up more board space than the accepted answer, but it was fun to think about:

schematic

simulate this circuit – Schematic created using CircuitLab

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