Logic gates whats the basic ones that you need

Thread Starter

roll cast

Joined Apr 3, 2011
11
I was doing a bit of looking into logic gates and found out that all of the most common gates can be made from AND, NOT and OR gates however does this rule apply for every gate or only the most common simple gates?

Thanks
 

t06afre

Joined May 11, 2009
5,934
The AND, NOT, and OR gates are the building blocks. With these gates you can create any logic function. If we go back a (very) long long time. The cheapest logic block was the NAND gate. So it was actually cost effective to build logic using only NAND chips. But still to day it is a typical question in digital electronics exams. You are presented a boolean equation. And asked to draw the circuit using only NAND gates
By the way. a very useful building block in digital electronics are the JK flop-flop. You should also get some of those.
 

SgtWookie

Joined Jul 17, 2007
22,210
You can also make any other logic gate with NOR gates.
NAND: http://en.wikipedia.org/wiki/NAND_logic
NOR: http://en.wikipedia.org/wiki/NOR_logic


One of the most handy logic ICs to have around is the 4093 quad Schmitt-trigger NAND gate. Various manufacturers use different prefixes for the 4000-series CMOS logic ICs, like CD, HEF, MC1, etc. Very few of the 4000-series ICs have Schmitt-trigger inputs; the 40106 hex Schmitt-trigger inverter is the only other one I can think of offhand.

74-series ICs are also handy, but their operating voltage range is more limited, and they are generally more power-hungry. If you are using battery power, you should consider the 4000-series.
 
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