74HC4520D (NEXPERIA)

The 74HC4520D is a dual 4-bit internally synchronous Binary Counter with two clock inputs (nCP0 and nCP1). It has buffered outputs from all 4-bit positions (nQ0 to nQ3) and an asynchronous master reset input (nMR). The counter advances on the low-to-high transition of nCP0 when nCP1 is high. It also advances on the high-to-low transition of nCP1 when nCP0 is low. Either nCP0 or nCP1 may be used as the clock input to the counter. The other clock input may be used as a clock enable input. A high on nMR, resets the counter (nQ0 to nQ3 = low) independent of nCP0 and nCP1. Inputs include clamp diodes. It enables the use of current limiting resistors to interface inputs to voltages in excess of VCC.