AA431 is a three terminal adjustable parallel regulator with guaranteed thermal stability over the entire operating range. With excellent conduction characteristics, low temperature coefficient, and low output impedance, it is an ideal substitute for Zener diodes in applications such as switching power supplies, chargers, and other adjustable voltage regulators.

        The output voltage of AA431 can be set to any value Vref (2.495V) and the corresponding maximum cathode voltage (36V). The AA431 precision reference voltage source provides two types of voltage tolerances: 0.5% and 1%. This chip is available in two packages: SOT-23 and TO92.

Internal structure diagram of AA431:

            Main characteristic parameters of AA431:

• Programmable precise output voltage 2.5V to 36V

• Low temperature deviation: typical value 5mV

• Low equivalent full range temperature coefficient

• Current absorbing capacity from 1 mA to 100 mA

• Low output noise

• Wide operating temperature range from minus 40 to 125 ℃

• ROHS/Halogen Free

            AA431 common Application circuit：