74AC138SJ

Signal Switches, Multiplexers, Decoders Overview

The onsemi 74AC138SJ is a high-speed 1-of-8 decoder/demultiplexer belonging to the 74AC logic series. It accepts three binary weighted address inputs (A0, A1, A2) and provides eight mutually exclusive active-LOW outputs (O0–O7). The device operates within a supply voltage range of 2.0 V to 6.0 V and supports an operating temperature range from -40°C to +85°C. It features multiple input enables for parallel expansion and outputs capable of sourcing or sinking 24 mA.

Signal Switches, Multiplexers, Decoders Feature Summary

• Accepts three binary weighted inputs to provide eight mutually exclusive active-LOW outputs when enabled.
• Features multiple input enables allowing easy parallel expansion to larger decoders using additional devices.
• Capable of functioning as an 8-output demultiplexer by utilizing one active LOW Enable input as the data input.

Signal Switches, Multiplexers, Decoders Applications

• High-speed bipolar memory chip select address decoding
• Parallel expansion to 1-of-24 or 1-of-32 decoders
• Demultiplexing applications

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify the specific package variant against the datasheet ordering information, as suffixes indicate different packaging options such as SOIC-16 rails or tape and reel quantities. Confirm that the required logic family matches the AC specifications rather than ACT, which has distinct input threshold requirements. Ensure the selected component meets the necessary environmental and electrical standards for the target application.

Signal Switches, Multiplexers, Decoders Selection Notes

Select this component for applications requiring high-speed decoding with low power consumption compared to older families. The wide supply voltage range allows compatibility with various system voltages. Consider the output drive capability of 24 mA for direct interfacing with loads. Verify that the package type aligns with the PCB layout constraints and assembly methods available.

Signal Switches, Multiplexers, Decoders Part Context

This device is part of the 74AC138 family, which includes variants like the 74ACT138. While sharing similar functional descriptions, the ACT version offers TTL-compatible inputs and different electrical characteristics. The AC series is optimized for speed and reduced current consumption, making it suitable for battery-powered or high-density digital systems requiring efficient address decoding.

Signal Switches, Multiplexers, Decoders Replacement Considerations

Direct substitutes include other 74AC138 variants from different manufacturers that adhere to the same JEDEC pinout and logical functionality. Cross-reference the package dimensions and electrical parameters to ensure compatibility. Note that 74ACT138 devices may require adjustments due to differing input voltage thresholds despite functional similarity.