Texas Instruments TL431ACD Adjustable Precision Shunt Regulator, SOIC-8

The Texas Instruments TL431ACD is a three-terminal adjustable precision shunt regulator, designed primarily for secondary side regulation in flyback switch-mode power supplies (SMPS). It provides a highly accurate and adjustable voltage and current reference, with an output voltage that can be precisely set to any value between its reference voltage (approximately 2.5V) and 36V using just two external resistors. This flexibility makes it an indispensable component in a wide range of precision electronic designs.

Its active output circuitry ensures a very sharp turn-on characteristic, offering superior performance as a direct replacement for Zener diodes in numerous applications. Key advantages include its low output impedance of just 0.2Ω typical and a low output noise profile, contributing to stable and clean voltage regulation. With a sink-current capability ranging from 1 to 100mA, it can handle substantial load variations while maintaining precise control.

Engineered for stability, the device features minimal output drift over temperature, ensuring reliable operation across its full specified temperature range. Its robust construction supports an operating virtual junction temperature of up to 150°C, making it suitable for demanding environments. The surface-mount SOIC-8 package is compact and designed for efficient PCB integration in modern electronics manufacturing.

Key Specifications & Features

• Voltage Reference Type: Adjustable Shunt Regulator
• Adjustable Output Voltage Range: 2.495V to 36V
• Typical Output Impedance: 0.2Ω
• Sink-Current Capability: 1mA to 100mA
• Initial Accuracy: 1%
• Operating Virtual Junction Temperature: Up to 150°C
• Package Type: SOIC (Small Outline Integrated Circuit)
• Pin Count: 8 Pins
• Mounting Style: Surface Mount (SMD)
• Operating Temperature Range: 0°C to 70°C

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