TL1431QLPR

Overview

The TL1431QLPR is an automotive-grade precision programmable reference from Texas Instruments, characterized for operation over the full temperature range of –40°C to 125°C. It features a typical reference input voltage (VI(ref)) of 2.5 V with an initial tolerance of 0.4%. The device supports an adjustable output voltage range from approximately 2.5 V to 36 V using two external resistors. It offers a sink current capability between 1 mA and 100 mA and exhibits a typical output impedance of 0.2 Ω. The component utilizes a TO-92 package.

Feature Summary

• Provides precise voltage referencing with specified thermal stability across automotive temperature ranges.
• Features active output circuitry that delivers fast turn-on characteristics for effective Zener diode replacement.
• Functions as a shunt regulator or error amplifier by maintaining regulation when cathode current exceeds minimum thresholds.

Applications

• Secondary side regulation in flyback switching mode power supplies
• Adjustable voltage and current referencing circuits
• Voltage monitoring systems requiring integrated reference
• Comparator applications utilizing internal reference threshold

Procurement Notes

Verify the specific suffix 'Q' confirms automotive qualification and the 'LP' suffix denotes the TO-92 package configuration. Confirm the datasheet revision matches the required specifications for your design. Ensure the operating temperature range aligns with the –40°C to 125°C characterization defined for the TL1431Q variant. Cross-reference pinout details for the TO-92 package to ensure correct board layout integration.

Selection Notes

Select this component when automotive reliability and wide temperature operation are required. The TO-92 package suits through-hole mounting applications where space allows. Consider the 0.4% initial tolerance if high accuracy is needed without external trimming. Evaluate the 1 mA to 100 mA sink current range against load requirements to ensure stable regulation under all expected operating conditions.

Part Context

The TL1431 series serves as a versatile precision programmable reference widely used in industrial and automotive electronics. The TL1431QLPR specifically addresses the needs of automotive environments, offering robust performance across extreme temperatures. It integrates a bandgap reference and error amplifier into a single shunt regulator device, simplifying circuit design for power supply feedback loops and voltage monitoring tasks.

Replacement Considerations

The TL1431Q is the direct automotive-grade equivalent within the family. Verify compatibility with standard TL431 designs, noting potential differences in initial tolerance and temperature coefficients between commercial and automotive grades. Ensure substitute parts match the TO-92 package dimensions and pinout configuration for direct footprint replacement.