How To Select Transient Voltage Suppressors

There are important Transient Voltage Suppressor (TVS) data sheet characteristics and ratings that require careful comparisons to circuitcomponent limitations and transient conditions before selecting the optimum component. When using these TVSs, the most important parameters are identified as the Rated Working Peak Voltage or Rated Standoff Voltage (VWM), the Peak Pulse Power Dissipation (PPP), Peak Impulse Current (IPP), and Clamping Voltage (VC). Further parameters are also described herein and how they might further influence selection of TVS components.

It is important to recognize that a TVS is primarily intended to serve as a shunt-voltage clamp across sensitive components in the circuit to prevent high voltage transients from damaging them. Until these transients occur, the TVS will be idling at very low standby current levels and appear "transparent" to the circuit. When a high voltage transient does occur, the device clamps the voltage by avalanche breakdown. Also see MicroNote 103 for further details.

SOURCE: Microsemi Corporation