HCF4516B - Presettable Binary UP/DOWN Counter, DIP-16, ST Microelectronics
It is a PRESETTABLE BINARY UP/DOWN COUNTER, consists of four synchronously clocked D-type flip-flops (with a gating structure to provide T-type flip-flop capability) connected as a counter. This counter can be cleared by a high level on the RESET line, and can be preset to any binary number present on the jam inputs by a high level on the PRESET ENABLE line. Synchronous cascading is accomplished by connecting all clock inputs in parallel and connecting the CARRY OUT of a less significant stage to the CARRY IN of a more significant stage.
HCF4516B can be cascaded in the ripple mode by connecting all clock inputs in parallel and connecting the CARRY OUT to the clock of the next stage. If the UP/ DOWN input changes during a terminal count, the CARRY OUT must be gated with the clock, and the UP/DOWN input must change while the clock is high. This method provides a clean clock signal to the subsequent counting stage.