SN74ACT573QDGSRQ1

Overview

The SN74ACT573QDGSRQ1 is an automotive-grade octal D-type transparent latch with 3-state outputs, designed for driving highly capacitive or low-impedance loads. It operates within a supply voltage range of 4.5V to 5.5V and accepts input voltages up to 5.5V. The device features a maximum propagation delay of 9.5ns at 5V and TTL-voltage compatible inputs. Packaged in a VSSOP-20 (DGS) format measuring 5.1mm x 4.9mm, it supports an operating temperature range from -40°C to +125°C.

Feature Summary

• Features 3-state outputs specifically engineered to drive high-capacitance or low-impedance loads without requiring interface components.
• Provides TTL-voltage compatibility on inputs while accepting full 5.5V logic levels.
• Includes active-low output enable (OE) and latch enable (LE) controls for precise data storage and bus isolation.

Applications

• Parallel data storage
• Digital bus buffer
• Buffer registers

Procurement Notes

Verify the specific package variant matches the design requirements, as the Q1 suffix denotes automotive qualification. Confirm that the ordering suffix corresponds to the desired tape-and-reel quantity and lead finish. Ensure the selected component meets the required thermal resistance metrics for the intended PCB layout and ambient conditions.

Selection Notes

Select this component when driving heavy capacitive loads or long traces where signal integrity is critical. The 3-state capability allows direct connection to shared buses without external pull-ups. Verify that the system supply voltage remains strictly between 4.5V and 5.5V to maintain specified timing and electrical characteristics.

Part Context

This part belongs to the SN74ACT573-Q1 family of automotive octal latches. It shares functional similarities with non-automotive catalog versions like the SN74ACT573 but includes enhanced reliability testing for automotive environments. The DGS package offers a compact surface-mount solution compared to larger through-hole alternatives.

Replacement Considerations

SN74ACT573QPWRQ1 (TSSOP-20)

FAQ

How does the OE pin affect internal latch operations?

The Output Enable (OE) pin only controls the state of the outputs. It does not affect the internal operation of the latches, allowing data to be retained or entered even when outputs are in the high-impedance state.

What is the recommended handling for unused inputs?

Unused inputs must never be left floating. They should be terminated to either VCC or ground using appropriate resistors to prevent undefined operational states and excessive power consumption.