Driving circuit for light-emitting diodes

摘要

A driving circuit for light-emitting diodes includes a power unit providing an input voltage, a voltage regulation unit providing a voltage-increasing loop and a voltage-decreasing loop and having an energy-storing capacitor with an intermediate voltage therebetween, a current control unit generating a driving current for the light-emitting diodes according to the intermediate voltage, and a switching control unit. The switching control unit generates a reference voltage based on the input voltage and compares the reference voltage with a feedback voltage associated with driving current. The switching control unit controls the voltage regulation unit to increase the intermediate voltage through the voltage-increasing loop when the feedback voltage is smaller than the reference voltage. The switching control unit controls the voltage regulation unit to decrease the intermediate voltage through the voltage-decreasing loop when the feedback voltage is larger than the reference voltage.

主权项

1. A driving circuit for light-emitting diodes (LED) driving an LED module comprising a plurality of LEDs, the driving circuit comprising:
a power source for providing an input voltage; a voltage regulator electrically connected to the power source and the LED module, the voltage regulator providing a voltage-increasing loop and a voltage-decreasing loop and having an energy-storing capacitor with an intermediate voltage therebetween; a current control unit electrically connected to the voltage regulator and the LED module, the current control unit generating a driving current for the light-emitting diodes according to the intermediate voltage; and a switching control unit electrically connected to the power source, the voltage regulator and the current control unit, the switching control unit configured to generate a reference voltage based on the input voltage and to compare the reference voltage with a feedback voltage associated with driving current; wherein the switching control unit controls the voltage regulation unit to increase the intermediate voltage through the voltage-increasing loop when the feedback voltage is smaller than the reference voltage, the switching control unit controls the voltage regulation unit to decrease the intermediate voltage through the voltage-decreasing loop when the feedback voltage is larger than the reference voltage.