Patent ID: 9462645
Filing Date: 2016-10-04
CPC Classification: H05B

Claim Text:
1. An LED driver circuit with stepwise adjustable power, in that comprising a constant current IC chip U 1 , a power supply unit connecting to the constant current IC chip U 1 , a switch control unit and a driving unit, wherein the driving unit connects to the switch control unit; the LED driver circuit also comprises a power regulation unit, and the power regulation unit connects to the constant current IC chip U 1 , the switch control unit and the driving unit; the power supply unit comprises a 300V voltage input, a resistor R 3 , a resistor R 4 , a resistor R 5 , a capacitor C 1 , a diode D 1 , a capacitor C 5 and a resistor R 10 ; an internal multiplier input pin MULT of the constant current IC chip U 1 connects to the 300V voltage input via the resistor R 4 and the resistor R 5 ; a zero current detection pin ZCD of the constant current IC chip U 1 is grounded via the resistor R 10 ; the capacitor C 5 is connected in parallel with two ends of the resistor R 10 ; the diode D 1 has a positive pole which is grounded and a negative pole which connects to the zero current detection pin ZCD of the constant current IC chip U 1 .