The 74HCT373 is a transparent octal D-type latch with 3-state outputs and a TTL input level. The device has inputs for latch enable (LE) and output enables (OE). When LE is HIGH, data from the inputs are routed to the latches.

Because the latches are transparent in this state, a latch output will change whenever its corresponding D-input changes. When LE is LOW, the latches store the information present at the inputs prior to the HIGH-to-LOW transition of LE. When OE is set to HIGH, the outputs enter a high-impedance OFF state.

The state of the latches is unaffected by the operation of the OE input. Clamp diodes are used as inputs. This allows for the use of current-limiting resistors to interface inputs to voltages greater than VCC.