General Description
The MM74HC161 and MM74HC163 synchronous presettable counters utilize advanced silicon-gate CMOS technology and internal look-ahead carry logic for use in high speed counting applications. They offer the high noise immunity and low power consumption inherent to CMOS with speeds similar to low power Schottky TTL. The HC161 and the HC163 are 4 bit binary counters. All flip-flops are clocked simultaneously on the LOW-to-HIGH transition (positive edge) of the CLOCK input waveform.

Features
■ Typical operating frequency: 40 MHz
■ Typical propagation delay; clock to Q: 18 ns
■ Low quiescent current: 80 µA maximum (74HC Series)
■ Low input current: 1 µA maximum
■ Wide power supply range: 2–6V