Patent ID: 8125160
Filing Date: 2012-02-28
Classification: H04N,H05B

Abstract:
1. A circuit for providing power to a light source, comprising: synchronization circuitry configured to receive a synchronization signal and determining whether said synchronization signal complies with at least one of a Phase Alternating Line (PAL) standard or a National Television System Committee (NTSC) standard, wherein said synchronization circuitry comprises flip-flop circuitry configured to receive said synchronization signal and a comparison result between a plurality of reference signals which include a predetermined DC reference signal and to generate a detection signal indicating whether said synchronization signal complies with said at least one of said PAL standard or said NTSC standard; and pulse width modulation circuitry configured to generate a pulse width modulation signal based on a frequency of said synchronization signal to adjust power of said light source.