Can TVS devices be used in series or in parallel?
Can TVS devices be used in series or in parallel?

Solution

Can TVS devices be used in series or in parallel?

1. Can TVS be used in series? Theoretically speaking, when the Vrwm of a single TVS device cannot be satisfied, it can be used in series. The Vrwm and Vbr of the whole circuit are respectively equal to the sum of the corresponding parameters of the two TVS devices. While Ipp and Pppm did not change much.

However, in practical applications, due to the large parameter range of TVS devices, the transient action time of TVS devices is not necessarily the same. Even if the same type of TVS devices are used in series, it may be difficult to guarantee their Parameter consistency, theoretical voltage superposition may not be possible in practice, and it is usually not recommended to use in series.

2. Can TVS be used in parallel? It is very rare to use TVS devices in parallel. In principle, parallel connection can increase the protection Ipp and Pppm, but in fact it is used in combination with TVS devices and other protective devices (such as pressure sensitive or gas discharge tubes); use the action time of different protective devices To realize the coordinated action of the front and rear stages, decoupling with resistance or inductance.

The parallel action time of TVS devices is in an order of magnitude, it is difficult to achieve decoupling, and it is also not recommended to use.