Working voltage switching circuit of relay, circuit board and equipment

The invention discloses a working voltage switching circuit of a relay, a circuit board and equipment, the working voltage switching circuit comprises a voltage output circuit and a voltage feedback circuit, the voltage output circuit comprises a voltage output end and a signal receiving end, and the voltage output end is used for applying voltage to two ends of a relay coil; the voltage feedback circuit comprises a voltage sampling end and a voltage feedback end, the voltage sampling end is connected with the voltage output end, and the voltage feedback end is connected with the signal receiving end; the control module in the working voltage switching circuit obtains different feedback voltages by triggering different level signals, and further outputs target voltages corresponding to the different feedback voltages, so that the power loss on a relay coil is reduced when the relay works in a pull-in manner and keeps pull-in, and the problems of serious heating of the coil and the like are avoided. 本申请公开了一种继电