Contents
What is MOV diode?
An MOV is a voltage dependent device which has an electrical behavior similar to back to back zener diodes. ▪ When exposed to high voltage transients, the MOV’s resistance. changes from a near open circuit to a very low value, thus clamping the transient voltage to a safe level.
How does MOV work?
The main function of MOV is to work as a surge suppressor. When the voltage across the varistor is below the clamping voltage then varistor will not conduct. The main feature of this kind of varistor is response time because the voltage spikes are shorted in nanoseconds with the device.
What is the use of MOV in circuit?
A Metal Oxide Varistor (MOV) is a protection component used in power supply circuits that is powered directly from AC mains. It is used to protect the circuit from high voltage spikes by varying its resistance.
How are TVS diodes different from MOV devices?
During ESD events, the complex impedance of the protection devices changes dynamically, and calling this specification Rdyn often confuses design engineers. During the first 10ns, other methods are needed to predict the voltages. TVS diodes tend to have lower dynamic resistance (Rdyn) than MOV devices.
How are silicon diodes and metal oxide varistors used?
Silicon diodes and metal-oxide Varistors are used to protect delicate circuit components from electrostatic discharge (ESD) or other transient events. These guidelines can be used when comparing two devices (TVS or MOV) of the same technology
Why are MOV devices used in power electronics?
MOV performance is affected by the volume of the device (Height × Length × Width). Large devices can handle very high voltage levels. For this reason, MOV devices are generally used to protect line powered circuitry. MOV devices are self-sacrificial.
How are protection devices used in TVS diodes?
Ideally, all of the energy flows through the protection device, defending the load from any damage. After the surge passes, the ideal device quickly returns to “Normal” mode, without any internal damage or changes in its performance. TVS semiconductor diodes are monolithic devices fabricated using standard semiconductor techniques.