SN54LS169B,SN54S169,SN74LS169B

These synchronous presettable counters feature an internal carry look-ahead for cascading in high speed counTIng applicaTIons. The 'LS169B and 'S169 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 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.

These counters are fully programmable; that is the outputs may each be preset to either level.