PROTECTION CIRCUIT FOR POWER SUPPLY WITH INDUCTIVE LOAD

摘要

PROBLEM TO BE SOLVED: To obtain a protection circuit for a power supply with an inductive load, wherein a closed circuit for absorbing the surge current of the inductive load can be composed of elements with a relatively small power consumption and the main power circuit does not need a diode for reverse current prevention with a large current capacity. SOLUTION: The protection circuit for a power supply with an inductive load energizes the inductive load 5 by a battery 1 via P-ch MOSFET 2P. The protection circuit is provided with an N-ch MOSFET 12N parallel connected with the P-ch MOSFET 2P or an inductive load 5. When the P-ch MOSFET 2P is turned off, the N-ch MOSFET 12N detects the surge voltage in the inductive load 5 and brings itself in conduction and thereby form a current closed circuit. Thus surge produced in the inductive load 5 is absorbed by the current closed circuit.