SHUNT REGULATORS

# Shunt Regulators

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## 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:

## Manufacturer Part Numbers

• 431: Very common shunt regulator.
• LM431: Shunt regulator from Texas Instruments based on the 431 series.

## Authors

### Geoffrey Hunter

Dude making stuff.