HD74HC669 - Hitachi Semiconductor

HD74HC669 Synchronous UP/Down Decade/4-bit binary Counter

This synchronous presettable decade counter features an internal carry look-ahead for cascading in highspeed counting applications. 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 countenable inputs and internal gating. This mode of operation hel.

Features

an internal carry look-ahead for cascading in highspeed counting applications. 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 countenable inputs and internal gating. This mode of operation helps eliminate the output counting spikes that are normally associated with asynchronous (ripple-clock) counters. A buffered clock input triggers the four master-slave flip-flops on the rising (positive going) edge of the clock waveform. This counter is fully programmable; that is, the outputs .