The MM74HC74A is a Dual D-Type Flip-Flop with Preset and Clear The MM74HC74A utilizes advanced silicon-gate CMOStechnology to achieve operating speeds similar to theequivalent LS-TTL part. It possesses the high noiseimmunity and low power consumption of standardCMOS integrated circuits, along with the ability to drive10 LS-TTL loads. This flip-flop has independent data, preset, clear, andclock inputs and Q and Q outputs. The logic levelpresent at the data input is transferred to the output duringthe positive-going transition of the clock pulse. Presetand clear are independent of the clock andaccomplished by a low level at the appropriate input. The 74HC logic family is functionally and pinout compatiblewith the standard 74LS logic family. All inputs areprotected from damage due to static discharge by internaldiode clamps to VCC and ground.