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# ALTERNATIVE LOGIC GATES

CONTENT

1. Description of Alternative Logic Gate
2. Types of Alternative Logic Gate
3. Symbols of Each Logic Gate
4. Input/Output Signals for: NAND, NOR Gates

## Description of Alternative Logic Gate

Although OR, AND, and NOT gate combinations are good enough for the construction of any logic operation, there are alternative methods that could be used. The alternative logic gates are NAND and the NOR logic gates. Alternative methods using NAND and NOR gates are more economical and therefore more widely used.

All logic operations can be performed with combinations of just NANDs or NORs, but a combination of NORs with NANDs is usually preferable to one provided just by NANDs.

## Types of Alternative Logic Gate

Basic digital logic gates perform logical operations using the following standard single logic gates:

(i) Logic “NAND” gate

(ii) Logic “NOR” gate

### (i) The Logic “NAND” Gate

The logic NAND gate is a combination of the digital logic AND gate with that of an inverter, or NOT gate connected together in series.

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