Schmitt-trigger noise immunity in a 74HC gate
The CD74HC132MT packs four independent 2-input NAND gates with Schmitt-trigger inputs into a single 14-SOIC package. The hysteresis on each input — 0.3V to 1.2V low threshold, 1.5V to 4.2V high threshold across the 2V to 6V supply range — means a slowly rising or noisy signal does not cause multiple output transitions at the switching point. This is the gate you reach for when a clean digital edge is needed from a bouncy switch contact or a long PCB trace picking up crosstalk.
Propagation delay and output drive at 6V
Maximum propagation delay is 21 ns at 6V with a 50 pF load — the fastest switching edge within the 74HC family at that supply voltage. Each output sources or sinks 5.2 mA, enough to drive a standard CMOS input on the same rail or a low-power LED indicator without a buffer. Quiescent current sits at 2 µA max, so the gate adds negligible standby draw in battery-powered designs.