Patent ID: 8014118
Filing Date: 2011-09-06
Classification: G09G

Abstract:
1. A load driving circuit comprising an output terminal for connection to a load; two main switch elements, including a low-side main switch element and a high-side main switch element having a totem pole structure and connected between a pair of drive voltage supply lines, at least one of the two main switch elements being connected to the output terminal; an overvoltage prevention switch configured to connect a control electrode and a low-potential-side control subject electrode of one of the two main switch elements; and a voltage control circuit including voltage-dividing components connected in series, each voltage-dividing component being one of a resistor and a capacitor, the voltage control circuit being configured to turn on the overvoltage prevention switch during a prescribed period at the time of potential variation at the output terminal, a first one of the voltage-dividing components being connected between a control terminal of the overvoltage prevention switch and the low-potential-side control subject electrode of the one main switch element and a second one of the voltage-dividing components being connected between the control terminal of the overvoltage prevention switch and the control electrode of the one main switch element, so that a potential at one end of the first one of the voltage-dividing components is applied at the control terminal of the overvoltage prevention switch and a potential at the other end of the first one of the voltage-dividing components is applied at the low-potential-side control subject electrode of the one main switch element.