Patent ID: 9041314
Filing Date: 2015-05-26
Classification: H02M,H05B,Y02B

Abstract:
1. An LED illuminating device comprising: a rectifying circuit which rectifies ac power and supplies power to a rectified output node; a switch element coupled with the rectified output node and a first node; a current detection resistor coupled with the first node and a second node; an inductor coupled with the first node and a first output node; a diode coupled with a second output node and the first node, an anode of the diode being coupled with the second output node; an output capacitor coupled with the first output node and the second output node; a light emitting diode coupled with the first output node and the second output node; and a control circuit coupled with the first node and the switch element, wherein the control circuit comprises: a driver circuit having an output coupled to the gate of the MOSFET and an input; a set/reset latch circuit having a first output coupled to the input of the driver circuit, a second output, a set terminal and a reset terminal; a first comparator circuit having an output coupled to the reset terminal, a first input and a second input; a second comparator circuit having an output coupled to the set terminal, a first input coupled to receive a first reference voltage and a second input coupled to the first node; an error amplifier circuit having an output coupled to the a second input of the first comparator circuit, a first input coupled to receive a second reference voltage and a second input coupled to the first node, and a ramp circuit comprising: