DM74LS191 - National Semiconductor

DM74LS191 Synchronous 4-Bit Up/Down Counters

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.

Features

Y Counts 8-4-2-1 BCD or binary Y Single down up count control line Y Count enable control input Y Ripple clock output for cascading Y Asynchronously presettable with load control Y Parallel outputs Y Cascadable for n-bit applications Y Average propagation delay 20 ns Y Typical clock frequency 25 MHz Y Typical power dissipation 100 mW Connection Diagram Dual-In-Line-Package TL F 6405-1 Order Number DM54LS190J DM54LS191J DM54LS190W DM54LS191W DM74LS190M DM74LS191M DM74LS190N or DM74LS191N See NS Package Number J16A M16A N16A or W16A C1995 National Semiconductor Corporation TL F 6405 RRD-B30.