Metal oxide varistor burn-in
Abstract
Varistor degradation from unipolar transient pulsing is described. Metal-Oxide varistors (MOVs) subjected to a single high-energy transient displayed an increase in standby current and a decrease in clamping voltage. The amount of degradation was dependent on the polarity of the measurement relative to the polarity of the pulsing, as well as the energy rating of the device. After one pulse, the clamping voltage is lower when measured at the port opposite to the pulsing than when measured at the same port which was pulsed. Polarization of permanent electric dipoles in the insulating intergranular matrix and the filling of traps at the metal oxide grain boundaries are discussed as possible mechanisms for the degradation.
- Publication:
-
Final Report
- Pub Date:
- June 1986
- Bibcode:
- 1986afwl.rept.....H
- Keywords:
-
- Burn-In;
- Metal Oxides;
- Varistors;
- Electric Potential;
- Grain Boundaries;
- Nonlinear Systems;
- Polarity;
- Pulses;
- Zinc Oxides;
- Electronics and Electrical Engineering