Patent ID: 7592792

Claim:
An inductive load current control circuit comprising: an input terminal that inputs an input voltage; an output terminal that outputs an output voltage; a reference power source that is a current source having a current driving capability of outputting a reference current; first and second switch elements that are connected in series between the input terminal and a ground potential; an inductive load that has one terminal connected to a connection point between the first switch element and the second switch element, and another terminal connected to the output terminal to output the output voltage; a third switch element that has one terminal connected to the connection point between the first switch element and the second switch element; a current comparator that has one terminal connected to an output terminal of the reference power source and another terminal connected to another terminal of the third switch element, the current comparator comparing a current driving capability of the third switch element with a current driving capability of the reference current to decide and output a magnitude relation; and a switch element control circuit that alternately controls a first state and a second state and controls transition from the second state to the first state according to an output of the current comparator, in the first state, the first switch element being turned on and the second switch element and the third switch element being turned off to cause a current to flow from the input voltage to the inductive load, in the second state, the first switch element being turned off and the second switch element and the third switch element being turned on to cause a current to flow from the ground potential to the inductive load through the second switch element by energy accumulated in the inductive load at the first state.