Patent ID: 7907376
Filing Date: 2011-03-15
Classification: H01L,H02M,H02P

Abstract:
1. A load control device comprising: a power source for supplying a power supply voltage; a control circuit that controls driving of a load; a protection circuit that monitors the power supply voltage supplied to the control circuit and stops control by the control circuit when the power supply voltage drops below a threshold value; a first wiring that supplies a current to the load from a terminal to which the power supply voltage is supplied, the first wiring including a smoothing inductor; and a second wiring that is directly connected to the terminal and supplies the power supply voltage to the control circuit from the terminal of the power supply voltage, the second wiring being different from the first wiring and connected between the smoothing inductor and the terminal of the power supply voltage, wherein the protection circuit has a means to provide the threshold value with a hysteresis characteristic having a width equal to or larger than a voltage drop level based on a wiring resistance of a path for supplying a driving current to the load and a maximum value of the driving current.