The MM74HC4020, MM74HC4040, are high speed binary ripple carry counters. These counters are implemented utilizing advanced silicon-gate CMOS technology to achieve speed performance similar to LS-TTL logic while retaining the low power and high noise immunity of CMOS. The MM74HC4020 is a 14 stage counter and the MM74HC4040 is a 12-stage counter. Both devices are incremented on the falling edge (negative transition) of the input clock, and all their outputs are reset to a low level by applying a logical high on their reset input.