SN74ACT138PWRQ1

Signal Switches, Multiplexers, Decoders Overview

The SN74ACT138PWRQ1 is an automotive-grade 3-to-8 decoder/demultiplexer featuring TTL-compatible CMOS inputs. It operates within a supply voltage range of 4.5V to 5.5V and supports continuous output drive currents of ±24mA at 5V, with short-burst capabilities up to ±75mA. The device provides fast propagation delays, typically ranging from 6.6ns to 11ns depending on the input path. It includes three enable inputs (G0, G1, G2) for flexible gating and is qualified under AEC-Q100 standards for Grade 1 temperature operation.

Signal Switches, Multiplexers, Decoders Feature Summary

• AEC-Q100 qualified for automotive applications with specified temperature grades and ESD classifications
• TTL-compatible CMOS inputs allow direct interfacing with legacy logic families
• Balanced push-pull outputs provide high current drive capability for transmission lines
• Wettable flank package options facilitate reliable soldering and automated optical inspection

Signal Switches, Multiplexers, Decoders Applications

• Memory device selection with shared data bus architectures
• Chip select signal generation to reduce required output counts
• Data routing and demultiplexing in automotive electronic control units

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify that the specific ordering suffix matches the required package type, as the Q1 series is available in both TSSOP and WQFN configurations. Confirm the presence of wettable flanks if automatic optical inspection compatibility is a design requirement. Ensure the selected variant meets the specific thermal and electrical constraints defined in the datasheet's absolute maximum ratings table.

Signal Switches, Multiplexers, Decoders Selection Notes

Select this component when designing systems requiring robust interface between 5V logic and lower voltage microcontrollers due to its TTL-compatible input thresholds. Consider the device's high output drive strength for applications involving long traces or heavy capacitive loads. Verify that the chosen package style aligns with the board layout constraints and manufacturing inspection capabilities regarding lead visibility.

Signal Switches, Multiplexers, Decoders Part Context

This part belongs to the SN74ACT138-Q1 family of automotive decoders. It shares functional logic with standard industrial counterparts but incorporates enhanced reliability features and qualification testing mandated for automotive environments. The 'Q1' designation indicates compliance with AEC-Q100 standards, distinguishing it from non-automotive variants like the SN74ACT138PWR.

Signal Switches, Multiplexers, Decoders Replacement Considerations

SN74ACT138WBQBRQ1

Signal Switches, Multiplexers, Decoders FAQ

How are unused inputs handled to prevent oscillation?

Unused TTL-compatible CMOS inputs must not be left floating. They should be terminated directly to VCC or ground, or connected via a pull-up/pull-down resistor to ensure valid logic states during operation.

What is the function of the G0, G1, and G2 pins?

These are output strobe inputs used to enable or disable the decoder outputs. G2 is active-high, while G1 and G0 are active-low. If any strobe condition is unmet, all outputs are forced to the high state regardless of address inputs.