Why NAND & NOR Gates are Necessary for LATCH Circuits

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TL;DR
why NAND AND NOR gates alone are used to form a LATCH circuit
Why we cannot make a LATCH circuit with logic gates other than NAND and NOR gates.?
 
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Avanthica said:
TL;DR Summary: why NAND AND NOR gates alone are used to form a LATCH circuit

Why we cannot make a LATCH circuit with logic gates other than NAND and NOR gates.?
I think you can. However, recognize that all combinatorial logic can be (in fact often are) constructed from NAND and NOR gates. The fundamental boolean operations are AND, OR, and INVERT (or NOT), everything can be constructed from these. For technical reasons, it is usually easier to just make NAND and NOR gates as the basis for all higher complexity digital circuits in ICs.
 
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Avanthica said:
Why we cannot make a LATCH circuit with logic gates other than NAND and NOR gates.?
Because you need an inverter somewhere in a latch. Try to design a latch without a NOT gate and see what happens.

A transistor with gain is inherently an inverter. To make an AND gate, you must build a NAND gate, then invert the output with a NOT. AND is therefore slower than NAND.
 
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