SN74ALS667DWRE4

Overview

The SN74ALS667DWRE4 is an 8-bit D-type transparent read-back latch with 3-state outputs manufactured by Texas Instruments. It belongs to the ALS logic series and features inverting outputs. The device operates within a supply voltage range of 4.5 V to 5.5 V and supports an operating temperature range of 0°C to 70°C. It utilizes a 24-pin Small-Outline (DW) package. Key electrical parameters include a propagation delay from data input to output ranging from 6 ns to 20 ns, low-level output current capability of 24 mA, and high-level output current of -2.6 mA.

Feature Summary

• Provides 3-state I/O-type read-back inputs for reading stored data onto the input data bus
• Features a bus-structured pinout suitable for bus-organized applications
• Includes preset and clear inputs for direct control of latch states

Applications

• Bus-structured memory storage systems
• Data latching circuits requiring read-back functionality
• High-speed digital logic interfaces

Procurement Notes

Verify that the ordering suffix 'RE4' corresponds to the specific tape-and-reel packaging variant rather than the standard tube configuration. Confirm RoHS compliance status and lead finish specifications against the latest Package Addendum documentation prior to procurement to ensure compatibility with assembly processes.

Selection Notes

Select this component when an 8-bit latch with inverted outputs and read-back capability is required. Ensure the design accommodates the 4.5 V to 5.5 V supply voltage range and the 0°C to 70°C operating temperature limits. Verify that the 24-pin SOIC package dimensions fit the target PCB layout constraints.

Part Context

This part is part of the SN74ALS666/667 family of 8-bit D-type transparent read-back latches. The SN74ALS667 variant specifically provides inverted outputs, whereas the SN74ALS666 offers true outputs. Both share identical pinouts and functional characteristics except for output polarity.

Replacement Considerations

SN74ALS667DW