The MC74AC161/74ACT161 and MC74AC163/74ACT163 are high-speed synchronous modulo-16 binary counters. They are synchronously presettable for application in programmable dividers and have two types of Count Enable inputs plus a Terminal Count output for versatility in forming synchronous multistage counters. The MC74AC161/74ACT161 has an asynchronous Master Reset input that overrides all other inputs and forces the outputs LOW. The MC74AC163/ 74ACT163 has a Synchronous Reset input that overrides counting and parallel loading and allows the outputs to be simultaneously reset on the rising edge of the clock.

Synchronous Counting and Loading
High-Speed Synchronous Expansion
Typical Count Rate of 125 MHz
Outputs Source/Sink 24 mA
ACT161 and ACT163 Have TTL Compatible Inputs
These devices are available in Pb-free package(s). Specifications herein apply to both standard and Pb-free devices.