Varistors

Varistors are a type of electronic component that can change their resistance depending on the voltage applied to them. They are also known as voltage-dependent resistors (VDRs). Varistors are mainly used to protect other devices from overvoltage and excess current by limiting the voltage and absorbing the energy. Varistors can prevent damage to sensitive circuits and components caused by power surges, spikes, or transients. Varistors are made of materials that have a nonlinear and non-ohmic current-voltage characteristic, such as metal oxides, silicon carbide, or zinc oxide.