SN74HCS139PWR

Overview

The SN74HCS139PWR is a dual 2-to-4 line decoder/demultiplexer featuring Schmitt-trigger inputs, housed in a 16-pin TSSOP package. It operates within a supply voltage range of 2 V to 6 V and supports an extended ambient temperature range from –40°C to +125°C. The device provides balanced CMOS push-pull outputs with an output drive capability of ±7.8 mA at 6 V. Electrical characteristics include typical input leakage current of ±100 nA and typical supply current of 100 nA. Propagation delays vary by supply voltage, ranging from 6 ns to 45 ns depending on conditions.

Feature Summary

• Schmitt-trigger inputs provide high noise immunity and tolerance for slow or noisy signal transitions.
• Balanced CMOS push-pull outputs ensure similar sourcing and sinking current capabilities.
• Dual independent channels allow simultaneous decoding or demultiplexing operations.

Applications

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

Procurement Notes

Verify the specific ordering suffix 'PW' corresponds to the TSSOP package variant when sourcing. Confirm that the component meets RoHS compliance standards as indicated in the packaging information. Ensure handling procedures account for electrostatic discharge sensitivity, adhering to the specified human-body model and charged-device model ratings provided in the datasheet specifications.

Selection Notes

Select this component when design requirements necessitate operation across a wide voltage range including 2 V and 6 V rails. The inclusion of Schmitt-trigger inputs makes it suitable for environments with significant signal noise or slow edge rates. Verify that the thermal resistance values for the TSSOP package align with the system's heat dissipation capabilities under maximum load conditions.

Part Context

This device belongs to the Texas Instruments SN74HCS series, which utilizes HCMOS technology to deliver high-speed performance with low power consumption. The HCS designation indicates the presence of Schmitt-trigger inputs, distinguishing it from standard HC logic families. The dual decoder architecture allows for efficient management of multiple peripheral devices using minimal control lines.

Replacement Considerations

The SN74HCS139D serves as a pin-compatible alternative packaged in SOIC format. Both variants share identical electrical specifications and functionality, differing only in physical package dimensions and thermal characteristics.