Varistors are nonlinear two-electrode semiconductor voltage-dependant resistors. The current in a varistor is proportional to applied voltage raised to a power. These devices are normally made of zinc ...

Higher voltages trigger the avalanche effect and cause the diode junctions to break down. As a rule, metal oxide varistors exhibit highly non-linear current-voltage characteristics. They have high ...

Most applications for varistors are in surge protection, protecting circuits from mains transients, inductive loads and from lightning. They’re usually placed across the circuit to be protected ...