TL431

The transistor TL431 is an adjustable zener diode. It is used in the role of a reference voltage source in circuits of various power supplies. Based on the TL431, it is possible to design all kinds of light and sound alarms. TL431 has three outputs: cathode, anode, input. With the help of such structures, it is possible to control a variety of different parameters, for example, voltage control.

It has following characteristics:
Output voltage: 2.5 ... 36 volts;
Output resistance: 0.2 Ohm;
Forward current: 1 ... 100 mA;
Error: 0.5%, 1%, 2%;

TL431 equivalents

Transistor KA431AZ;
Transistor HA17431VP;
Transistor LM431BCM.