LED BACKLIGHT DRIVE CIRCUIT, BACKLIGHT MODULE, AND LIQUID CRYSTAL DISPLAY APPARATUS

摘要

An LED backlight drive circuit comprises a power supply module (10), an LED light bar (20) coupled to the power supply module (10), and a constant-current drive chip (30) driving the LED light bar (20). The constant-current drive chip (30) comprises an under-voltage protection pin (31) receiving an under-voltage protection signal. An over-voltage collection module (40) and an under-voltage collection module (50) are coupled to an input end of the power supply module (10). An output voltage of the under-voltage collection module (50) is directly coupled to the under-voltage protection pin (31). The LED backlight drive circuit further comprises a comparison module (60). A reference voltage is coupled to a first input end of the comparison module (60), and the over-voltage collection module (40) is coupled to a second input end. When a voltage output by the over-voltage collection module (40) exceeds the reference voltage, the comparison module (60) outputs an under-voltage protection signal to the under-voltage protection pin (31).