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HD74HC173
4-bit D-type Register (with 3-state Outputs)
Description
The four D type Flip-Flops operate synchronously from a common clock. The 3-state outputs allow the device to be used in bus organized systems. The outputs are placed in the 3-stage mode when either of the output disable pins are in the logic high level. The input disable allows the flip-flops to remain in their present states without having to disrupt the clock. If either of the 2 input disables are taken to a logic high level, the Q outputs are fed back to the inputs, forcing the flip-flops to remain in the same state. Clearing is enabled by taking the clear input to a logic high level. The data outputs change state on the positive going edge of the clock.