XNOR gate (exclusive NOR)
XOR followed by NOT: with two inputs, the output is 1 when they are equal.
Truth table
| A | B | Y |
|---|---|---|
| 0 | 0 | 1 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Pins
2–8 inputs on the left, one output on the right.
How to use it
Equality checker: one XNOR per bit, then AND all the results to test whether two numbers are equal.
Usage example
Outputs 1 when the inputs are equal (both 1 here) — handy for checking whether two bits match.