Backlight constant current driver board and liquid crystal display television

Backlight constant current driver board comprises boost circuit, constant current control circuit, switchover switch circuit, and light strip socket, connects to backlight light strip via light strip socket. Boost circuit boosts input voltage before outputting output voltage and transmits via light strip socket as power supply to backlight light strip. Switchover switch circuit controls, according to PWM signal and power supply voltage, connection or disconnection of current loop between backlight light strip and ground. Constant current control circuit monitors and keeps constant current magnitude of backlight light strip in switchover switch circuit. By switchover switch circuit, during system standby, formation of current loop between backlight light strip and ground is prevented so backlight light strip does not emit light, thus solving problems of screen emitting dim lights when existing LCD television standby or constant current drive control chip not working.