Tl431 is produced by Texas Instruments, a tl431 is a three-terminal adjustable shunt reference with good thermal stability. Its output voltage can be arbitrarily set to any value from Vref (2.5V) to 36V with two resistors. The device's typical dynamic impedance is 0.2Ω, which can be used in many applications to replace Zener diodes, such as digital voltmeters, op amp circuits, adjustable voltage supplies, switching power supplies, and more.
Below are some related circuit diagrams of tl431.
Tl431 internal structure diagram:
Tl431 symbol and internal block diagram
Tl431 internal circuit diagram
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