LED BACKLIGHT DRIVING CIRCUIT, LIQUID CRYSTAL DISPLAY DEVICE, AND DRIVING METHOD

摘要

Disclosed are an LED backlight driving circuit, a liquid crystal display device, and a driving method. The LED backlight driving circuit comprises a power supply. An output capacitor and an LED light strip connected in series with a first controllable switch are disposed in parallel between an output terminal and a grounding terminal of the power supply. The LED backlight driving circuit further comprises a first comparator. The first comparator has a negative electrode connected to a first reference voltage, a positive electrode coupled to the output terminal of the power supply, and an output terminal coupled to a control terminal of the first controllable switch. When the voltage at the positive electrode of the first comparator exceeds the voltage at the negative electrode, the output terminal of the first comparator drives the first controllable switch to be switched on. In the present invention, the LED light strip is controlled to be switched on only at a preset voltage, so that even if the output capacitor stores charges, the LED cannot be driven to be lightened; only when the startup is completed, and the output voltage reaches a preset voltage value, the first controllable switch is switched on, thereby solving the problem of flickering during startup.