The IN74AC161 is identical in pinout to the LS/ALS161, HC/HCT161. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALS outputs.
The IN74AC161 is programmable 4-bit synchronous modulo-16 counter that feature parallel Load, asynchronous Reset, a Carry Output for cascading and count-enable controls.
The IN74AC161 is binary counter with asynchronous Reset.

• Outputs Directly Interface to CMOS, NMOS, and TTL
• Operating Voltage Range: 2.0 to 6.0 V
• Low Input Current: 1.0 µA; 0.1 µA @ 25° C
• High Noise Immunity Characteristic of CMOS Devices
• Outputs Source/Sink 24 mA