Patent ID: 7902772
Filing Date: 2011-03-08
Classification: H05B

Abstract:
1. A circuit for driving a lamp, comprising: a reference voltage output unit, the reference voltage output unit providing a reference voltage; a voltage sensor, the voltage sensor detecting a sensed voltage corresponding to a status of a lamp, the status of the lamp including an open-circuit status and a closed-circuit status; a comparator, the comparator comparing the sensed voltage with the reference voltage and outputting a result indicating the status of the lamp; an enable signal output unit for outputting an enable signal; and an enable signal control unit, the enable signal control unit receiving the result indicating the status of the lamp, the enable signal control unit disabling the enable signal output unit when the result indicates the status of the lamp being the open-circuit status, wherein the voltage sensor includes first and second voltage-dividing circuits connected to both electrodes of the lamp, respectively, and the sensed voltage includes first and second sensed voltages output from the first and second voltage-dividing circuits, respectively, and wherein the first and second sensed voltages are compared with the reference voltage to thereby detect the lamp being open-circuit.