LED driving control circuit and LED driving circuit

摘要

The present invention provides an LED (Light-Emitting Diode) driving control circuit for controlling a converting circuit to transform an input power source into an output voltage for driving an LED module. The LED module has a plurality of LED strings. The LED driving control circuit includes a voltage detecting circuit and a feedback control circuit. The voltage detecting circuit has a plurality of detection circuits, and each detection circuit is coupled to a terminal of the corresponding LED string to determine whether a voltage of the terminal is higher or lower than a preset value. The voltage detecting circuit generates a feedback signal according to the determination results. The feedback control circuit controls the converting circuit to modulate the output voltage according to the feedback signal.

主权项

1. An LED (Light-Emitting Diode) driving control circuit for controlling a converting circuit to convert a power from a power source into an output voltage to drive an LED module which has a plurality of LED strings, the LED driving control circuit comprising:
a voltage detecting circuit comprising a plurality of detection circuits, wherein each of the detection circuits is coupled to a terminal of a corresponding LED string in the LED module for determining whether the terminal is higher than or lower than a preset value, thereby generating a determination result, and each of the detection circuits generates a feedback signal in response to the determination result; and a feedback control circuit controlling the converting circuit to modulate the output voltage according to the feedback signal, wherein each of the detection circuit comprises a switch, a current source and a waveform modulation circuit, and the switch is coupled with the current source in series, and a control end of the switch is coupled to the terminal of the corresponding LED string, and an input end of the waveform modulation circuit is coupled to a connecting node between the switch and the current source and generates the feedback signal at a first logical level or a second logical level in response to that a state of the switch.