Control method, control circuit, backlight integration circuit and terminal equipment

Abstract

The invention provides a control method, a control circuit, a backlight integration circuit and terminal equipment. The control method comprises the following steps of acquiring current brightness of a backlight light source; if the current brightness is greater than preset brightness, making a largest limitation current of a backlight driving circuit increase to a first limitation current and adjusting a duty ratio of a pulse width modulation circuit so that the current brightness matches with the first limitation current; if the current brightness is less than or equal to the preset brightness, making the largest limitation current of the backlight driving circuit reduce to a second limitation current and adjusting the duty ratio of the pulse width modulation circuit so that the current brightness matches with the second limitation current. In embodiments of the invention, through comparing the current brightness of the backlight light source to the preset brightness, according o a comparison result, the largest limitation current of the backlight driving circuit is increased or reduced; simultaneously, the adjusted largest limitation current is used to adjust the duty ratio, the current is maintained to be stable so that the brightness of the backlight light source possesses a large regulation and control scope.

Description

technical field [0001] The invention relates to the field of communication technology, in particular to a control method, a control circuit, a backlight integrated circuit and terminal equipment. Background technique [0002] Electronic displays such as liquid crystal displays (LCDs) usually appear in many mobile electronic devices. The brightness of the LCD screen depends on the current of the light-emitting diode (LED) string in the backlight assembly. It usually consists of one or more backlight LED strings. The LED string is It is driven by the backlight driver chip. For the backlight driver chip with pulse width modulation PWM control method, the internal integrated current source is usually adjusted by the pulse width modulation circuit, and the current on the output LED light string is indirectly adjusted to control the brightness of the LED light string. [0003] The pulse width modulation PWM backlight drive circuit usually has a hardware current limiting resistor R...

AI Technical Summary

Problems solved by technology

[0011] The purpose of the present invention is to provide a control method, control circuit, backlight integrated circuit and terminal equipment, which solves the problem in the prior art that the maximum brightness of the screen is too low or the minimum brightness is too small due to the setting of the external maximum current limit

Images