TL431MFDT-QR

Overview

The TL431MFDT-QR is a three-terminal shunt regulator from the Nexperia TL431 family, designed for precision voltage reference applications. It features an adjustable output voltage range between 2.495 V and 36 V, set by two external resistors. This specific variant offers a B-Grade reference voltage tolerance of 0.5% and operates within an extended temperature range of -40 °C to +125 °C. The device utilizes mirrored pinning configuration in a SOT-23 (TO-236AB) surface-mount package. It is qualified under AEC-Q101 standards for automotive reliability.

Feature Summary

• Programmable cathode voltage up to 36 V via external resistor divider
• High accuracy with 0.5% reference voltage tolerance at B-Grade level
• Extended industrial temperature operation capability from -40 °C to +125 °C
• Automotive grade qualification compliant with AEC-Q101 standards

Applications

• Shunt regulator circuits
• Precision current limiter designs
• Isolated feedback loops for Switch Mode Power Supplies (SMPS)
• Precision constant current sink implementations

Procurement Notes

Verify component authenticity through official Nexperia channels or authorized distributors. Confirm the presence of the AEC-Q101 qualification marking on the datasheet before integration. Ensure the mirrored pinning configuration matches the target PCB footprint design. Check for any Product Change Notifications (PCN) regarding manufacturing site updates. Validate that the specific suffix QR meets the reel packaging requirements for automated assembly lines.

Selection Notes

Select this part when high precision is required alongside automotive durability. The 0.5% tolerance suits tight regulation needs compared to standard grades. The mirrored pinning requires careful schematic review against standard pinouts. Verify thermal management capabilities for the SOT-23 package in high-current scenarios. Consider the extended temperature range benefits for harsh environment deployments.

Part Context

This component belongs to the widely adopted TL431 family of programmable zener diodes. It serves as a direct replacement for legacy discrete transistor-based references. The MFDT suffix indicates the specific mirrored pinout variant within the SOT-23 package family. It complements other grades like ACDBZR or BIDBZR offering different tolerance and temperature specifications.

Replacement Considerations

Direct substitutes include TL431BMFDT for non-automotive use or TL431AMFDT for lower tolerance requirements. Verify pin compatibility due to the unique mirrored configuration. Cross-reference with TL431QDBZR if standard pinning is acceptable but similar performance is needed.