Method and device for overvoltage protection at a bus interface of a time switch board in an exchange

摘要

The invention discloses a method for overvoltage protection at bus interface of a time switch circuit board in an exchange. The method comprises adding a voltage-limited protection circuit, unidirectional or bidirectional, between every driver/receiver signal line of TS-BUS and the earth. The invention also discloses a device for overvoltage protection according to the method. The device comprises a printed board that has socket connectors on two sides and overvoltage protection circuits on the middle, the overvoltage protection circuits are voltage-limited circuits and each of them is connected between every driver/receiver line of TS-BUS and the earth in a bypass mode.