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