This circuit is a synchronous reversible up down counter The 191 is a 4-bit binary counter Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change simultaneously when so instructed by the steering logic This mode of operation eliminates the output
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54191 DM54191 DM74191 Synchronous Up Down 4-Bit Binary Counter with Mode Control
June 1989
54191 DM54191 DM74191 Synchronous Up Down 4-Bit Binary Counter with Mode Control
General Description
This circuit is a synchronous reversible up down counter The 191 is a 4-bit binary counter Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change simultaneously when so instructed by the steering logic This mode of operation eliminates the output counting spikes normally associated with asynchronous (ripple clock) counters
The outputs of the four master-slave flip-flops are triggered on a low-to-high level transition of the clock input if the enable input is low A high at the enable input inhibits counting Level changes at either the enable inpu
DM54191 Datasheet
