An exemplary backlight control circuit (20) includes at least two sampling circuits (21), at least two feedback circuits (22), and a PWM IC (23). Each of the sampling circuits includes a sampling output (210) and a backlight lamp (211). The PWM IC includes a current sense pin (230). The at least two feedback circuits correspond to the at least two sampling circuits, respectively. Each of the feedback circuits includes a resistor (222) and a diode (223) electrically coupled in parallel. The sampling output is configured to output a first voltage when the backlight lamp is in a normal working state, and output a second voltage when the backlight lamp has an open circuit. One terminal of the diode is electrically coupled to the sampling output of a corresponding one of the sampling circuits, and an opposite terminal of the diode is electrically coupled to the current sense pin.

 
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