SN74HC161DR

4位同步二进制计数器

description

These synchronous, presettable counters feature an internal carry look-ahead for application in high-speed counting designs. The ’HC161 devices are 4-bit binary counters. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change coincident with each other when so instructed by the count-enable ENP, ENT inputs and internal gating. This mode of operation eliminates the output counting spikes that are normally associated with synchronous ripple-clock counters. A buffered clock CLK input triggers the four flip-flops on the rising positive-going edge of the clock waveform.

Wide Operating Voltage Range of 2 V to 6 V

Outputs Can Drive Up To 10 LSTTL Loads

Low Power Consumption, 80-µA Max ICC

Typical tpd = 14 ns

±4-mA Output Drive at 5 V

Low Input Current of 1 µA Max

Internal Look-Ahead for Fast Counting

Carry Output for n-Bit Cascading

Synchronous Counting

Synchronously Programmable