74AHCT138D-Q100J

Signal Switches, Multiplexers, Decoders Overview

The Nexperia 74AHCT138D-Q100J is a high-speed Si-gate CMOS 3-to-8 line decoder/demultiplexer with inverting outputs. It accepts three binary weighted address inputs (A0, A1, A2) and provides eight mutually exclusive outputs (Y0 to Y7) that are LOW when selected. The device features three enable inputs: two active LOW (E1, E2) and one active HIGH (E3). Qualified to AEC-Q100 Grade 1 standards, it operates within a supply voltage range of 4.5 V to 5.5 V and supports an ambient temperature range from -40 °C to +125 °C.

Signal Switches, Multiplexers, Decoders Feature Summary

• Automotive qualification compliant with AEC-Q100 Grade 1 standards for extended temperature operation.
• TTL-compatible input levels enabled by the HCT logic series architecture.
• Schmitt-trigger action on all inputs ensures tolerance for slower rise and fall times.
• Multiple enable inputs facilitate easy parallel expansion to larger decoding configurations.

Signal Switches, Multiplexers, Decoders Applications

• Memory chip select decoding
• Demultiplexing data streams using enable inputs as strobes
• Parallel expansion into 1-of-32 decoders

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify the specific suffix J against the manufacturer's current ordering information to confirm package type and tape/reel specifications. Confirm AEC-Q100 Grade 1 qualification status matches project requirements. Ensure the SO16 package variant aligns with PCB footprint constraints. Cross-reference the latest datasheet revision for any updates to electrical characteristics or pinning definitions before finalizing procurement.

Signal Switches, Multiplexers, Decoders Selection Notes

Select this component when TTL-level interface compatibility is required alongside automotive reliability standards. The AHCT series bridges CMOS performance with TTL input thresholds. Verify that the 4.5 V to 5.5 V supply voltage range fits the system power rails. Consider the multiple enable inputs for complex decoding needs rather than simpler decoder alternatives.

Signal Switches, Multiplexers, Decoders Part Context

This part belongs to the Nexperia 74AHC/AHCT138-Q100 family of 3-to-8 line decoders. It shares functional similarities with other members like the 74AHC138D-Q100 but differs in input voltage compatibility. The Q100 suffix denotes automotive-grade qualification, distinguishing it from standard commercial variants while maintaining pin compatibility with Low Power Schottky TTL devices.

Signal Switches, Multiplexers, Decoders Replacement Considerations

Direct substitutes include the 74AHCT138PW-Q100 in TSSOP16 packaging or the 74AHCT138BQ-Q100 in DHVQFN16 packaging. Non-Nexperia equivalents must be verified for identical AEC-Q100 Grade 1 qualification and pinout compatibility.

Signal Switches, Multiplexers, Decoders FAQ

How does the 74AHCT138D-Q100J handle demultiplexing?

It functions as an eight-output demultiplexer by utilizing one of the active LOW enable inputs as the data input, while the remaining enable inputs serve as strobes.

What is the function of the enable inputs?

The device has three enable inputs: two active LOW (E1, E2) and one active HIGH (E3). All outputs remain HIGH unless E1 and E2 are LOW and E3 is HIGH.