IDT74FCT139TQ

Overview

The IDT74FCT139TQ is a dual 1-of-4 decoder/driver manufactured by Integrated Device Technology. It utilizes Fast CMOS technology and operates within a supply voltage range of 4.5 V to 5.5 V, with a nominal rating of 5 V. The device features two independent decoders, each accepting two binary weighted inputs and providing four mutually exclusive active LOW outputs. It includes an active LOW enable for each decoder. The component is housed in a 16-pin plastic small outline package (PDSO16) and supports surface mount assembly.

Feature Summary

• Dual independent 1-of-4 decoding functionality with active LOW outputs
• Active LOW enable control for individual decoder sections
• Fast CMOS construction ensuring low power consumption and high speed
• Compatible with TTL input and output logic levels

Applications

• Address decoding in microprocessor-based systems
• Memory chip select generation
• Control signal distribution in industrial automation
• Data routing in communication equipment

Procurement Notes

Verify the specific suffix 'TQ' against official IDT documentation to confirm pinout and package dimensions, as variations exist within the FCT series. Ensure compliance with RoHS directives if required, noting that some legacy FCT parts may not be compliant. Confirm lead finish and moisture sensitivity level prior to placement on the PCB.

Selection Notes

Select this component when dual independent decoding is required in a compact surface-mount form factor. It serves as a replacement for older ABT logic families while offering lower power dissipation. Verify that the 5V supply voltage aligns with the system design and that the drive current capabilities meet the load requirements of the connected circuitry.

Part Context

This part belongs to the IDT 74FCT family of high-speed CMOS logic devices. The FCT series is designed to provide performance comparable to bipolar logic but with CMOS power efficiency. The 139 function code specifically denotes a dual 1-of-4 decoder, a standard configuration used widely in digital logic applications for selecting one of four output lines based on binary inputs.

Replacement Considerations

Cross-reference with IDT54FCT139 variants for radiation-tolerant options or other packages like SOIC and DIP. Check for direct pin-compatible alternatives from other manufacturers supporting the 74FCT standard, ensuring voltage and speed grade compatibility.