SN74HCS238QPWRQ1

Overview

The SN74HCS238QPWRQ1 is an automotive-qualified 3-to-8 line decoder and demultiplexer manufactured by Texas Instruments. It operates within a supply voltage range of 2 V to 6 V and supports an ambient temperature range from -40°C to +125°C. The device features Schmitt-trigger inputs for noise rejection and provides balanced CMOS push-pull outputs capable of ±7.8 mA drive current at 6 V. Propagation delay ranges from 7 ns to 54 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
• Schmitt-trigger inputs provide tolerance for slow or noisy input signals
• Balanced CMOS push-pull outputs ensure similar sourcing and sinking capabilities

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 'PW' corresponds to the TSSOP-16 package variant. Confirm AEC-Q100 qualification requirements match the target automotive grade. Ensure design accounts for the recommended operating conditions regarding supply voltage and thermal resistance metrics provided in the datasheet.

Selection Notes

Select this component when a high-speed decoder with Schmitt-trigger inputs is required for automotive environments. The wide voltage range supports various logic levels. Consider the TSSOP-16 package constraints and thermal characteristics during PCB layout planning to ensure reliable operation under maximum load conditions.

Part Context

This part belongs to the SN74HCS238-Q1 family, which includes variants in SOIC, WQFN, and SOT packages. The HCS series denotes high-speed CMOS technology with Schmitt-trigger inputs. The 'Q1' suffix indicates automotive qualification, distinguishing it from standard commercial logic devices.

Replacement Considerations

SN74HCS238PW-Q1 (TSSOP-16)

FAQ

How do the Schmitt-trigger inputs benefit signal integrity?

They allow for slow or noisy input signals by providing hysteresis, making the device tolerant to input transitions that might otherwise cause undefined states.

What is the function of the strobe inputs G1, G0, and G2?

These inputs control the output state. When any strobe is active, all outputs are forced low; otherwise, only the selected address output goes high.