Load control device

Abstract

To provide a load control device with which it is possible to detect a disconnection of GND wiring during regular operation.SOLUTION: Provided is a load control device 10 that includes a plurality of drive circuits of half-bridge structure that drive each of a plurality of inductive loads (solenoids 21, 22, 23) that are connected at one end to ground, one of the drive circuits being composed of a high-side MOSFET 31 and a low-side MOSFET 41 that are connected in series between a power supply input terminal TIN and a ground terminal TGND, the connection point of the high-side MOSFET 31 and low-side MOSFET 41 being connected to an output terminal TOUT1 to which the other end of the solenoid 21 is connected. The load control device 10 further includes a control circuit 50 that causes the drive circuits to stop operating when the IC ground potential VSUB of the ground terminal TGND exceeds the output potential VOUT1 of the output terminal TOUT1.SELECTED DRAWING: Figure 1

Claims

1. It incorporates multiple half-bridge drive circuits, each driving a plurality of inductive loads, one end of which is connected to ground. Each drive circuit consists of a high-side MOSFET and a low-side MOSFET connected in series between a common power input terminal and a common ground terminal. In each of the multiple drive circuits, the connection point between the high-side MOSFET and the low-side MOSFET is connected to an output terminal that is connected to the other end of each of the corresponding multiple inductive loads, in a load control device, A load control device comprising a control circuit that stops the operation of a drive circuit when the IC ground potential of the ground terminal exceeds the output potential of one of the drive circuits' output terminals when the corresponding inductive load is off.

2. The load control device according to claim 1, characterized in that it comprises a disconnection detection circuit for detecting a disconnection between the grounding terminal and ground, a first detection circuit for detecting one of the output potentials, a second detection circuit for detecting the IC ground potential, and a comparator that compares the output potential detected by the first detection circuit and the IC ground potential detected by the second detection circuit and outputs the comparison result to the control circuit.

3. The load control device according to claim 2, characterized in that the first detection circuit and the second detection circuit detect the one output potential and the IC ground potential, respectively, with reference to the power supply potential of the power supply input terminal.

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