Patent ID: 7986108
Filing Date: 2011-07-26
Classification: H05B

Abstract:
1. A start-up feedback circuit in a light-emitting diode (LED) driver, the start-up feedback circuit comprising at least one feedback sub-circuit comprising: a first current unit biased by a ground voltage, for asserting a first current; a second current unit for asserting a second current according to the first current; a third current unit for receiving an LED feedback voltage to assert the first current and a first control voltage; a fourth current unit for receiving the first control voltage to assert a third current mirrored from the second current and to induce a fourth current corresponding to the first control voltage; and a mirroring unit for asserting the fourth current and mirroring the fourth current to assert an output current corresponding to the fourth current, the output current being converted into a feedback voltage for boost of an output voltage of the LED driver and the LED feedback voltage corresponding to the output voltage.