SHUNT REGULATORS
Shunt Regulators
Article by:Geoffrey Hunter
Date Published: | |
Last Modified: |
Contents
Overview
Architectures
- Two-pin shunt regulators
- Three-pin shunt regulators
Three-Pin Shunt Regulators
A three-pin shunt voltage regulator is typically drawn as a Zener diode with a third pin coming from the middle and out to the side.
This can be confusing, as a three-pin shunt regulator is an IC (integrated circuit) that typically contains an op-amp, and BJT transistor along with the Zener! This is also reflected by the U
IC designator prefix which is commonly used for these devices. The following image shows what actually is inside one of these devices:

The internal functional diagram of a three-pin shunt regulator. Note that there is much more to one of these than just a simple Zener diode! Image from https://www.ti.com/lit/ds/symlink/lm431.pdf, retrieved 2021-01-26.
Manufacturer Part Numbers
- 431: Very common shunt regulator.
- LM431: Shunt regulator from Texas Instruments based on the 431 series.
Authors

This work is licensed under a Creative Commons Attribution 4.0 International License .
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