A backlight constant current driver board and LCD TV

Abstract

The invention discloses a backlight constant current drive board and a liquid crystal television. The backlight constant current drive board includes a Boost voltage boosting circuit, a constant current control circuit, a switch circuit and a lamp bar socket; the backlight constant current drive board passes through the light bar The socket is connected to the backlight strip; the Boost circuit boosts the input voltage and outputs the output voltage, which is transmitted to the backlight strip through the light strip socket; the switching circuit controls the voltage flowing through the backlight strip according to the PWM signal and the power supply voltage. On-off of the loop between the current and the ground; the constant current control circuit monitors the current of the backlight strip in the switch circuit according to the PWM signal and the EAN signal and makes it constant. By switching the switch circuit when the system is in standby, the current of the backlight light bar cannot form a loop with the ground, and the backlight light bar does not emit light; thereby solving the problem of the screen when the existing LCD TV is in standby or the constant current drive control chip does not work. There is a dimming problem.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a backlight constant current drive board and a liquid crystal television. Background technique [0002] In the era of meager profits, cost-effectiveness is no longer a slogan, it has been fully implemented in actual work. From large LCD screens to small components, with the continuous cost optimization, high cost performance has become an eternal theme in the development of power supplies. Common packages in the development of constant current drive control chips include QFP (Quad Flat Package)-44, SOP (Small Out-Line Package, small outline package)-32, SOP-24, SOP-16 , SOP-8, TSOP (Thin Small Outline Package, thin small size package)-6, etc. The package of the chip has a great relationship with the price. The smaller the package, the fewer the number of pins, and the cheaper the price. [0003] With the development of TV audio-visual product screens, backlight technology has...

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Problems solved by technology

[0005] In view of the deficiencies in the prior art above, the purpose of the present invention is to provide a backlight constant current driver board and an LCD TV to solve the problem of dimming of the screen when the existing LCD TV is in standby or when the constant current driver control chip is not working. The problem

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