The 74HCT4040N is a 12-stage Binary Ripple Counter with a clock input (CP\\), an overriding asynchronous master reset input (MR) and twelve parallel outputs (Q0 to Q11). The counter advances on the high-to-low transition of CP\\. A high on MR clears all counter stages and forces all outputs low, independent of the state of CP\\. Each counter stage is a static toggle flip-flop. Inputs include clamp diodes that enable the use of current limiting resistors to interface inputs to voltages in excess of VCC.