CD40192BMS

CD40192BMS CD40193BMS December 1992 CMOS Presettable Up/Down Counters (Dual Clock With Reset) Description CD40192BMS Presettable BCD Up/Down Counter and the CD40193BMS Presettable Binary Up/Down Counter each consist of 4 synchronously clocked, gated “D” type flip-flops connected as a counter. The inputs consist of 4 individual jam lines, a PRESET ENABLE control, individual CLOCK UP and CLOCK DOWN signals and a master RESET. Four buffered Q signal outputs as well as CARRY and BORROW outputs for multiple-stage counting schemes are provided. The counter is cleared so that all outputs are in a low state by a high on the RESET line. A RESET is accomplished asynchronously with the clock. Each output is individually programmable asynchronously with the clock to the level on the corresponding jam input when the PRESET ENABLE control is low. The counter counts up one count on the positive clock edge of the CLOCK UP signal provided the CLOCK DOWN line is high. The counter counts down one count on the positive clock edge of the CLOCK DOWN signal provided the CLOCK UP line is high. The CARRY and BORROW signals are high when the counter is counting up or down. The CARRY signal goes low one-half clock cycle after the counter reaches its maximum count in the count-up mode. The BORROW signal goes low one-half clock cycle after the counter reaches its minimum count in the countdown mode. Cascading of multiple packages is easily accomplished without the need for additional external circuitry by...