MM54HC173/MM74HC173TRI-STATEÉ Quad D Flip-FlopGeneral Des criptionThe MM54HC173/MM74HC173 is a high speed TRI-STATEQUAD D TYPE FLIP-FLOP that utilizes advanced silicongateCMOS technology. It possesses the low power consumptionand high noise immunity of standard CMOS integratedcircuits, and can operate at speeds comparable tothe equivalent low power Schottky device. The outputs arebuffered, allowing this circuit to drive 15 LS-TTL loads. Thelarge output drive capability and TRI-STATE feature makethis part ideally suited for interfacing with bus lines in a busoriented system.The four D TYPE FLIP-FLOPS operate synchronously froma common clock. The TRI-STATE outputs allow the deviceto be used in bus organized systems. The outputs areplaced in the TRI-STATE mode when either of the two outputdisable pins are in the logic ``1'' level. The input disableallows the flip-flops to remain in their present states withouthaving to disrupt the clock. If either of the 2 input disablesare taken to a logic ``1'' level, the Q outputs are fed back tothe inputs, forcing the flip flops to remain in the same state.Clearing is enabled by taking the CLEAR input to a logic ``1''level. The data outputs change state on the positive goingedge of the clock.The 54HC/74HC logic family is functionally as well as pinoutcompatible with the standard 54LS/74LS logic family.All inputs are protected from damage due to static dischargeby internal diode clamps to VCC and ground.