Description The LM431 is a 3-terminal adjustable shunt regulator with ensured temperature stability over the entire temperature range of operation. The output voltage may be set at any level greater than 2.5 V (VREF) up to 36 V merely by selecting two external resistors that act as a voltage divided network. Due to the sharp turnon characteristics this device is an excellent replacement for many Zener diode applications. Features 1• Average Temperature Coefficient 50 ppm/°C • Temperature Compensated for Operation Over the Full Temperature Range • Programmable Output Voltage • Fast Turnon Response • Low-Output Noise • Low-Dynamic Output Impedance • Available in Space-Saving SOIC-8, SOT-23, and TO-92 Packages Applications • Adjustable Voltage or Current Linear and Switching Power Supplies • Voltage Monitoring • Current Source and Sink Circuits • Circuits Requiring Precision References • Zener Diode Replacements