The AP431S/AP431SH is a 3-terminal adjustable shunt regulator with guaranteed thermal stability over a full operation range. It features sharp turn-on characteristics, low-temperature coefficient and low output impedance, which makes it ideal substitute for Zener diode in applications such as switching power supply, charger and other adjustable regulators.

The AP431S/AP431SH has the same electrical specifications as the industry standard 431 except that it features a low minimum cathode current for regulation. The typical value of 50μA makes the parts ideal for very low power dissipation applications. The output voltage of the AP431S/AP431SH can be set to any value between VREF (2.5V/2.495V) and the corresponding maximum cathode voltage (36V).

The AP431S/AP431SH is offered in two grade initial voltage tolerance at +25°C, 0.5% and 1%. This IC is available in 3 packages: TO-92 (Ammo Packing), SOT23 and SOT89.