- 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.
- Silicon Controlled Rectifiers (SCRs)
- Shift Registers
- Peltiers (Thermoelectric Cooler)
- Inrush Current
- Electropermanent Magnets (EPMs)