SN74ACT573QWRKSRQ1

Overview

The SN74ACT573QWRKSRQ1 is an automotive-grade octal D-type transparent latch with 3-state outputs, manufactured by Texas Instruments. It operates within a supply voltage range of 4.5V to 5.5V and supports input voltages up to 5.5V. The device features a maximum propagation delay of 9.5ns at 5V and TTL-voltage compatible inputs. Designed for driving highly capacitive or low-impedance loads, it provides continuous output currents of ±24mA. The component is housed in a 20-pin VQFN (RKS) package measuring 4.5mm x 2.5mm and functions reliably across an operating temperature range of -40°C to +125°C.

Feature Summary

• Features 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads.
• Inputs accept voltages up to 5.5V, ensuring compatibility with TTL voltage levels.
• Includes a buffered output-enable input to place outputs in normal logic states or high-impedance state.

Applications

• Parallel data storage
• Digital bus buffer

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the SN74ACT573-Q1 series includes multiple options such as VSSOP, TSSOP, and VQFN. Confirm that the RKS package designation aligns with your PCB footprint requirements. Ensure the automotive grade (-Q1) qualification meets your system's reliability standards. Check the latest Package Information Addendum for current moisture sensitivity levels and lead finish specifications before finalizing procurement.

Selection Notes

Select this component when designing systems requiring high-speed data latching with strong drive capabilities for low-impedance loads. The ACT series offers faster switching speeds compared to standard HC or HCT families, making it suitable for applications where signal integrity over longer traces is critical. Consider the thermal resistance characteristics of the VQFN package if operating near maximum junction temperatures. Verify that the 4.5V to 5.5V supply range matches your system's power architecture.

Part Context

This part belongs to the SN74ACT573-Q1 family of automotive octal D-type transparent latches. The -Q1 suffix indicates compliance with AEC-Q100 standards for automotive applications. The device is part of Texas Instruments' broader portfolio of logic ICs designed for robust performance in demanding environments. It serves as a key component for managing data flow in complex digital systems requiring reliable storage and buffering.

Replacement Considerations

Catalog versions like SN74ACT573 are available but lack automotive qualification. Military versions include SN54ACT573. Non-Q1 variants may not meet the same reliability standards for automotive use. Ensure any substitute maintains the 3-state output functionality and similar electrical characteristics to avoid redesigning interface circuits.

FAQ

How does the output-enable (OE) pin affect internal latch operations?

The OE pin controls the external output state but does not affect the internal operation of the latches. Data can be entered or retained while the outputs are in the high-impedance state.

What is the recommended handling for unused inputs on this device?

Unused inputs must not be left floating. They should be terminated to either VCC or ground using a pull-up or pull-down resistor, typically around 10kΩ, to prevent undefined operational states and oscillations.