General description

The 74HC573; 74HCT573 is a high-speed Si-gate CMOS device and is pin compatible

with Low-power Schottky TTL (LSTTL).

The 74HC573; 74HCT573 has octal D-type transparent latches featuring separate D-type

inputs for each latch and 3-state true outputs for bus oriented applications. A latch enable

(LE) input and an output enable (OE) input are common to all latches.

When LE is HIGH, data at the Dn inputs enter the latches. In this condition the latches are

transparent, i.e. a latch output will change state each time its corresponding D input

changes.

When LE is LOW the latches store the information that was present at the D-inputs a

set-up time preceding the HIGH-to-LOW transition of LE. When OE is LOW, the contents

of the 8 latches are available at the outputs. When OE is HIGH, the outputs go to the

high-impedance OFF-state. Operation of the OE input does not affect the state of the

latches.

The 74HC573; 74HCT573 is functionally identical to:

• 74HC563; 74HCT563, but inverted outputs

• 74HC373; 74HCT373, but different pin arrangement