SNJ54HC138J

Signal Switches, Multiplexers, Decoders Overview

The SNJ54HC138J is a military-grade 3-to-8 decoder and demultiplexer manufactured by Texas Instruments. It operates within a supply voltage range of 2 V to 6 V and supports an operating temperature range from -55 °C to 125 °C. The device features three binary select inputs (A, B, C) and three enable inputs (one active-high G1, two active-low G2A/G2B). It provides eight active-low outputs (Y0-Y7), where only the selected output is driven low while others remain high. Packaged in a 16-pin ceramic dual in-line package (CDIP), it offers typical propagation delays of 15 ns at 5 V and low power consumption with maximum input current of 1 µA.

Signal Switches, Multiplexers, Decoders Feature Summary

• Provides three binary select inputs to decode into one of eight active-low outputs
• Incorporates three enable inputs (one active-high, two active-low) for cascading or data reception control
• Designed for high-speed memory decoding and data-routing applications requiring short propagation delay times
• Capable of driving up to 10 LSTTL loads with balanced output drive

Signal Switches, Multiplexers, Decoders Applications

• High-speed memory decoders
• Data-transmission systems
• LED matrix displays
• Servers and white goods
• Power infrastructure and building automation

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify the specific ordering suffix 'J' corresponds to the CDIP package variant when sourcing. Confirm that the component meets the required military-grade environmental specifications, including the extended temperature range of -55 °C to 125 °C. Ensure compatibility with the system's supply voltage requirements, which must fall between 2 V and 6 V. Check for any specific handling precautions related to the ceramic package type during assembly.

Signal Switches, Multiplexers, Decoders Selection Notes

Select this component for designs requiring robust performance in harsh environments due to its wide temperature rating. The HC logic family offers low power consumption suitable for battery-operated or energy-efficient systems. Consider the CDIP package if through-hole mounting or hermetic sealing is necessary. Verify that the active-low output polarity aligns with the downstream circuit requirements, as the selected line goes low while others stay high.

Signal Switches, Multiplexers, Decoders Part Context

This part belongs to the SNx4HC138 family of 3-to-8 decoders and demultiplexers. The 'SNJ' prefix indicates a military-grade version produced by Texas Instruments, distinguished from commercial variants by stricter reliability standards and extended temperature capabilities. It shares functional compatibility with other HC series decoders but is optimized for high-performance memory systems where minimal system decoding delay is critical.

Signal Switches, Multiplexers, Decoders Replacement Considerations

SNJ54HC138W

Signal Switches, Multiplexers, Decoders FAQ

How many enable inputs does the SNJ54HC138J have?

It has three enable inputs: one active-high (G1) and two active-low (G2A and G2B).

What is the output state of non-selected lines?

All non-selected outputs remain in a high state, while only the single selected output is pulled low.

Can unused inputs be left floating?

No, all unused inputs must be held at VCC or GND to ensure proper device operation and prevent undefined states.