资 源 简 介
CD4510B Presettable BCD Up/Down Counter and the CD4516 Presettable Binary Up/Down Counter consist of four synchronously clocked D-type flip-flops (with a gaTIng structure to provide T-type flip-flop capability) connected as counters. These counters 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. The CD4510B will count out of non-BCD counter states in a maximum of two clock pulses in the up mode, and a maximum of four clock pulses in the down mode.
If the CARRY-IN input is held low, the counter advances up or down on each posiTIve-going clock transiTIon. 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.