LED backlight driving circuit and liquid crystal device

摘要

A LED backlight driving circuit is disclosed. The LED backlight driving circuit includes a boost circuit for converting an input voltage to an output voltage for a LED unit, a driving IC for controlling the boost circuit such that the boost circuit converts the input voltage to the output voltage for the LED unit, a discharging module for releasing charges stored within the boost circuit after the driving circuit is turned off, and a detecting module for detecting a voltage at an output end of the boost circuit and then for generating enable signals for controlling the operations of the driving IC. The LED backlight driving circuit is capable of detecting a discharging state of the boost circuit after being quickly rebooted. The driving circuit can be rebooted only if the output voltage is smaller than a reference voltage as the charges stored within the boost circuit is released. As such, the flashing issue is avoided. In addition, the liquid crystal device including the above LED backlight driving circuit is also disclosed.

主权项

1. A LED backlight driving circuit, comprising:
a boost circuit for converting an input voltage to an output voltage for a LED unit; a driving IC for controlling the boost circuit such that the boost circuit converts the input voltage to the output voltage for the LED unit; a discharging module for releasing charges stored within the boost circuit after the driving circuit is turned off; and a detecting module for detecting a voltage at an output end of the boost circuit and then for generating an enable signals connecting to the driving IC, the driving IC begins operations when the enable signals are at high level, and the driving IC stops operations when the enable signals are at low level; wherein one reference voltage is configured within the detecting module, the detecting module generates the enable signals at low level when the voltage at the output end of the boost circuit is larger than or equal to the reference voltage, and the detecting module generates the enable signals at high level when the voltage at the output end of the boost circuit is smaller than the reference voltage; and wherein the detecting module comprises a turn-on module for generating enabling signals and a switch module, the switch module is controlled by the enabling signals, the switch module is turned on when the enabling signals are at low level and the detecting module begins to detect the voltage at the output end of the boost circuit, the switch module is turned off when the enabling signals are at high level and the detecting module stops detecting the voltage at the output end of the boost circuit.