DM54LS191 Datasheet | National Semiconductor

DM54LS190 DM74LS190 DM54LS191 DM74LS191 Synchronous 4-Bit Up Down Counters with Mode Control May 1989 DM54LS190 DM74LS190 DM54LS191 DM74LS191 Synchronous 4-Bit Up Down Counters with Mode Control General Description These circuits are synchronous reversible up down counters The LS191 is a 4-bit binary counter and the LS190 is a BCD 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...