Protection circuit of electronic transformer

The utility model relates to an electronic transformer, in particular to the field of protection circuits for the electronic transformer. The protection circuit disposed between a rectifier circuit and a half-bridge inverter circuit of a main circuit of the electronic transformer comprises a sampling circuit, a bleeder circuit, a working circuit and a control circuit which are connected sequentially, and the sampling circuit and the control circuit are both connected with the half-bridge inverter circuit. Compared with the prior art, the protection circuit has the advantages that the circuit easily realizes overload protection, short circuit protection and over temperature protection by cooperation of the sampling circuit, the bleeder circuit, the working circuit and the control circuit.