8-bit identity comparison in a through-hole DIP
The Texas Instruments SN74HC688N is an 8-bit identity comparator from the 74HC family, comparing two 8-bit words and asserting an active-low output when they match. The 8 µA quiescent current keeps the static power draw negligible in always-on monitoring circuits.
Parametric fit for timing and temperature
For a 5 V system driving a 50 pF bus, the output settles within 36 ns, so the downstream latch must wait at least that long before reading the result.