主权项 |
1. A light source driving circuit for powering a first light source and a second light source by a DC (direct current) voltage, comprising:
a first control circuitry coupled to said first light source and said second light source; and a second control circuitry coupled to said first light source and said second light source, wherein if said DC voltage is within a first range, then said first control circuitry controls a first switch and said second control circuitry controls a second switch to turn on said first light source and to regulate a current flowing through said first light source, wherein said first switch and said second switch are coupled to said first light source, wherein if said DC voltage is within a second range, then said first control circuitry controls a third switch and said second control circuitry controls a fourth switch to turn on said first light source and said second light source and to regulate a current flowing through said first light source and said second light source, wherein said third switch and said fourth switch are coupled to said second light source. |