Quad XNOR with open-drain outputs — bus-level logic without contention
Supply range is 2V to 6V.
Open-drain output — what it buys you on the bus
Open-drain output sinks 5.2 mA per output. The high level is set by an external pull-up resistor.
Propagation delay and timing margin
Maximum propagation delay is 23 ns at 6V supply with a 50 pF load.
Package and mounting — 14-DIP for prototyping and retrofit
The SN74HC266N comes in a 14-lead plastic DIP (0.300" body width, 7.62 mm pitch) for through-hole soldering. That footprint is breadboard-friendly and easy to hand-solder, which is why this package persists in maintenance spares, lab prototypes, and retrofit of legacy boards where the original surface-mount gate has been replaced with a DIP adapter. The supplier device package is 14-PDIP, identical in footprint to the industry-standard 14-pin DIP.