SN74HCS139QPWRQ1

Overview

The SN74HCS139QPWRQ1 is an automotive-qualified dual 2-to-4-line decoder/demultiplexer from Texas Instruments. It operates within a supply voltage range of 2 V to 6 V and supports ambient temperatures from -40°C to +125°C. The device features Schmitt-trigger inputs for noise tolerance and balanced CMOS push-pull outputs capable of ±7.8 mA drive current at 6 V. Propagation delay ranges from 6 ns to 45 ns depending on voltage and temperature. It is housed in a 16-pin TSSOP package.

Feature Summary

• AEC-Q100 qualified for automotive applications with specified temperature grades and ESD protection levels.
• Schmitt-trigger inputs provide high noise immunity and support slow or noisy input signals without excessive power consumption.
• Balanced CMOS push-pull outputs deliver symmetric sourcing and sinking capabilities for robust signal driving.

Applications

• Memory device selection with shared data bus
• Reducing required number of outputs for chip select applications
• Routing data

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the Q1 series includes both SOIC and TSSOP variants. Confirm that the component meets AEC-Q100 Grade 1 requirements for your target operating temperature range. Ensure design validation accounts for the specific thermal resistance values associated with the selected package style during implementation.

Selection Notes

Select this component when designing systems requiring multiple independent decoding channels within a single integrated circuit. The inclusion of Schmitt triggers makes it suitable for environments with significant electrical noise or slow signal transitions. Verify that the output drive capability aligns with the load requirements of the connected memory or peripheral devices.

Part Context

This part belongs to the SN74HCS139-Q1 family of logic ICs designed specifically for automotive electronics. It provides two independent decoding functions, allowing for efficient management of address lines in complex digital architectures. The HCS designation indicates the use of HCMOS technology with Schmitt-trigger inputs, distinguishing it from standard HC series components.

Replacement Considerations

SN74HCS139QDRQ1 (SOIC Package)

FAQ

How do Schmitt-trigger inputs affect power consumption?

Unlike standard CMOS inputs, holding a Schmitt-trigger input at a valid voltage level other than VCC or ground does not cause huge increases in power consumption, though dynamic current may increase with slow transitioning signals.

What is the recommended handling for unused inputs?

Unused inputs must be terminated to either VCC or ground to prevent undefined operational states caused by floating voltages. They should not be left unconnected.