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.

FEATUREs
• 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 are Pb−Free Devices