Difference between revisions of "Gate"
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The first gates were built out of [[vacuum tube]]s; these were replaced with discrete [[transistor]]s. Larger logical elements, starting with [[flip-flop]]s, but including such things as [[counter]]s, [[shift register]]s, [[multiplexer]]s, etc, were built out of gates. | The first gates were built out of [[vacuum tube]]s; these were replaced with discrete [[transistor]]s. Larger logical elements, starting with [[flip-flop]]s, but including such things as [[counter]]s, [[shift register]]s, [[multiplexer]]s, etc, were built out of gates. | ||
Latest revision as of 12:06, 14 May 2021
A gate is the lowest level logical (as opposed to analog) circuit element. It takes a limited number of inputs, performs some operation on them, and produces an output (sometimes, the output and its negation).
Typical gates are:
- NOT (also known as an 'inverter')
- AND
- OR
- NAND (AND with inverted output)
- NOR (similar)
The first gates were built out of vacuum tubes; these were replaced with discrete transistors. Larger logical elements, starting with flip-flops, but including such things as counters, shift registers, multiplexers, etc, were built out of gates.
The next step was the creation of integrated circuits; the first ones each held a number of gates, but quickly the larger elements were then built as ICs too.
