MM54HC190 MM74HC190 MM54HC191 MM74HC191 January 1.
National Semiconductor
MM54HC190 - Up/Down Counters
MM54HC190 MM74HC190 MM54HC191 MM74HC191 January 1988 MM54HC190 MM74HC190 Synchronous Decade Up Down Counters with Mode Control MM54HC191 MM74HC191 S.
