Texas Instruments TL431 Adjustable Precision Shunt Regulator, SOT-23

The Texas Instruments TL431 is a highly precise, adjustable shunt regulator offering exceptional thermal stability and wide configurability. It is engineered to replace zener diodes in numerous circuit designs, providing superior performance with a typical output impedance of just 0.2Ω. Its active output circuitry creates an extremely sharp turn-on characteristic, ensuring reliable and stable voltage reference points.

A key advantage is its adjustable output voltage, which can be set to any value between a reference voltage (Vref) of approximately 2.5V and 36V using only two external resistors. This flexibility makes it an indispensable component for designing custom voltage thresholds and regulation points. The device boasts a sink-current capability ranging from 1 to 100mA, accommodating a wide variety of load conditions.

Performance and Reliability

Designed for demanding environments, the TL431 features low output drift over temperature, guaranteeing stable operation across its full temperature range of -40°C to 125°C. This is complemented by low output noise, contributing to clean and precise voltage regulation in sensitive applications. It is a green product, manufactured without antimony or bromine (Sb/Br).

Key Specifications and Applications

• Reference Voltage Range: Adjustable from 2.495V to 36V.
• Initial Accuracy: High precision with 0.5% accuracy.
• Temperature Coefficient: A low 92ppm/°C ensures minimal performance variation with temperature changes.
• Package: Supplied in a compact, surface-mount SOT-23-3 package, ideal for space-constrained PCB designs.

This component is a fundamental building block in power management systems, finding critical use in adjustable power supplies, switching power supplies, and onboard regulation circuits. Its robustness and precision also make it suitable for automotive, aerospace, defence, military, and a