Application of TVS diode in AC and DC circuits

Application of TVS diode in AC and DC circuits

TVS is an efficient protection element. If the poles are affected by reverse transient high energy, they can absorb surges at a very fast speed, forming effective protection for later circuits, suitable for power products, communication equipment, household appliances, etc.

Applications for diodes:

1. Application in AC circuits

If applied to an AC circuit, it is usually bidirectional polarity due to voltage surges from both directions. The figure below shows an application example of bidirectional TVS diode in an AC circuit. Here, the role of the TVS diode is to effectively suppress the shock pulse caused by the power grid. When the voltage is overvoltage, VRMW rises to the breakdown voltage and is broken down. In this case, a breakdown current will appear. Once the peak of iPP is reached, the voltage across will be clamped below VC. This protects the rear circuitry, including the rectifier bridge, capacitors, and components behind.

2. Application in DC circuits

In terms of DC, TVS diode can also be unidirectional, TVS and output load can be connected in parallel, and the load can be DC power supply or other output systems. It should be noted that the large reverse working voltage of the TVS  is at least 1.2 times the input voltage of the circuit, so the circuit is more reliable.

Diodes are widely used in DC, especially ESD protection. Portable devices are very sensitive to ESD and can efficiently absorb pulses by utilizing the ultrafast nature of TVS diode.

Diodes are also widely used in DC fields, such as transistor protection, integrated circuit protection, various load outputs, etc.