CD4021BM

CD4021BM is an 8-level CMOS static shift register. Each register level is a D-type flip-flop. In addition to the output form of the 8th level, the 6th and 7th levels can also provide "Q" output. In CD4021B, the serial input is synchronized with the clock, and the parallel input is asynchronous. In both types, the entrance is controlled by the parallel/serial control input. When the parallel/serial control input is low, the data and the clock line are shifted synchronously and serially shifted into the 8-level register. When the parallel/serial control input is high, the data is blocked to the 8-level register through the parallel input line and synchronized with the positive transition of the clock line.