CD74HC238PW

Overview

The CD74HC238PW is a high-speed CMOS logic device manufactured by Texas Instruments, functioning as a 3-to-8 line decoder or demultiplexer. It operates within a supply voltage range of 2 V to 6 V and features three binary address inputs (A0, A1, A2) that select one of eight outputs. The component utilizes a TSSOP-16 surface-mount package and supports a wide operating temperature range from -55°C to +125°C. Key electrical specifications include a propagation delay of 30 ns and output drive capabilities sufficient for ten low-power Schottky TTL loads.

Feature Summary

• Provides active-high decoding functionality where the selected output transitions high while others remain low when enabled.
• Includes two active-low enable inputs and one active-high enable input to facilitate cascading multiple units.
• Delivers high-speed performance comparable to low-power Schottky TTL while maintaining standard CMOS power consumption characteristics.

Applications

• Memory address decoding in digital systems
• Data routing and distribution networks
• Cascaded decoding configurations requiring multiple enable pins

Procurement Notes

Verify current production status as the component may be subject to obsolescence notices. Confirm package integrity upon receipt, ensuring the TSSOP-16 housing matches specified dimensions. Validate RoHS compliance documentation against regulatory requirements for your specific deployment region before final integration.

Selection Notes

Select this part when active-high decoding is required rather than the standard active-low configuration found in HC138 variants. Ensure the design accommodates the 2V to 6V supply range and accounts for the 30 ns propagation delay in timing-critical paths. Verify that the TSSOP-16 footprint aligns with existing PCB layout constraints.

Part Context

This device belongs to the Texas Instruments CD74HC series of high-speed CMOS logic components. It serves as the functional counterpart to the HC138, distinguished primarily by its inverted output logic state. The series is designed to bridge the performance gap between standard CMOS and legacy TTL technologies, offering faster switching speeds without significant power penalty.

Replacement Considerations

CD74HC238M96 is listed as a substitute option. Verify pinout compatibility and logical inversion differences when replacing with similar decoders like the HC138 series.