A method for reducing backlight power consumption

Abstract

The present invention relates to the field of backlight driver technology, and in particular to a method for reducing backlight power consumption. This method addresses the problem in the prior art of LCD products not distinguishing between the on / off times of screen displays, resulting in high power consumption. A solution is proposed, comprising signal output control based on TFTTiming parameters, controlling the backlight off in the Vblanking region based on the displayed Vblanking and Vdisplay conditions, and comprising a TE mode and a Vsync signal mode. This method fully utilizes the characteristics of TFT display drivers, does not increase hardware costs, and enables precise backlight on / off control through software debugging. Compared to traditional LED backlight dimming methods, this method better matches TFT signal characteristics and is more energy-efficient.

Description

Technical Field

[0001] The present invention relates to the field of backlight driving, and in particular to a method for reducing backlight power consumption. Background Art

[0002] With the development of LED backlight technology, it has been widely adopted in almost all LCD display products. Compared with CCFL backlights, it features a simpler structure, thinner modules, and a low-voltage DC drive circuit. This makes it simpler to design, energy-efficient, and has a longer lifespan. Existing backlight adjustment methods typically use a PWM pulse duty cycle to adjust LED brightness. When the PWM signal is high, the LED turns on, and when it is low, the LED turns off. However, this method does not differentiate between the on and off times of the display. Therefore, this solution proposes a method to reduce backlight power consumption. Summary of the Invention

[0003] The present invention proposes a method for reducing backlight power consumption. By precisely controlling the backlight on / off time, the present invention achieves a more controllable power saving mode and increases a certain contrast without affecting the LCD display performance.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for reducing backlight power consumption includes controlling signal output based on TFT Timing parameters and controlling backlight shutdown in the V blanking region based on the displayed V blanking and V display conditions. The method includes two modes: TE mode and Vsync signal mode. In TE mode, the LCD turns on the TE output and connects the TE output to the dimming control pin of the LED driver circuit.

[0006] In the V sync signal mode, the V sync signal is connected to the dimming control pin of the LED Driver circuit at the system end.

[0007] Through the above technical solution, the characteristics of TFT display driver are fully utilized without increasing hardware costs. Precise backlight switch control can be performed through software debugging. Compared with traditional LED backlight dimming methods, it better matches the characteristics of TFT signals and is more energy-efficient.

[0008] As a further improvement to the above solution, when using TE mode, the software setting turns on TE. When the LED Driver dimming control pin receives the TE trigger signal, the LED backlight is turned off. When TE is restored, the LED dimming is synchronously restored to its original state.

[0009] Through the above technical solution, the backlight switch can be accurately controlled using the TE signal.

[0010] As a further improvement to the above solution, when using the V sync signal, the LED backlight is turned off when the LED Driver dimming control pin receives the V sync trigger signal. When the V sync is restored, the LED dimming synchronization is restored to the original state.

[0011] Through the above technical solution, the backlight switch can also be accurately controlled using the V Sync signal.

[0012] As a further improvement of the above solution, the TFT Timing parameters include V front porch, V backporch, V sync pulse, and V display active, wherein the sum of V front porch, V back porch, and V sync pulse is V Blanking.

[0013] Through the above technical solution, the backlight switch can be conveniently adjusted according to the TFT Timing parameters.

[0014] As a further improvement of the above solution, the backlight is turned off during the V Blanking period and turned on during the V displayactive period, and the backlight power saving ratio of a frame is the ratio of V blanking to the entire frame.

[0015] With the above technical solution, since the backlight is turned off in the blanking area, the black screen becomes darker, thereby improving the contrast.

[0016] As a further improvement of the above solution, in the V Blanking region, the backlight switch is synchronously controlled through the V Sync signal or the TE signal.

[0017] Through the above technical solution, precise backlight switch control can be performed by using software debugging without increasing hardware costs.

[0018] As a further improvement to the above solution, BL on represents turning on the backlight, and BL off represents turning off the backlight. BL off is set according to the V blanking time, and energy saving is achieved according to the ratio of BL off time to (BL on + BL off) time. The formula is as follows:

[0019] Energy saving ratio = .

[0020] The above technical solution can effectively make the backlight of the LCD screen more energy-saving.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. Make full use of the characteristics of TFT display driver, without increasing hardware costs, and use software debugging to perform precise backlight switch control. At the same time, because the backlight is turned off in the blanking area, the black screen becomes darker, thereby improving the contrast.

[0023] 2. Compared with the traditional LED backlight dimming method, it is more compatible with TFT signal characteristics and more energy-efficient, especially for high-brightness products. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the synchronization between the LED backlight switch and the TFT signal of the present invention;

[0025] Figure 2 This is a schematic diagram showing TFT Timing parameters. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0027] Example 1

[0028] Please combine Figure 1-2 , Figure 1 In the figure, number 1 represents the output of the TFT signal in the vertical direction, number 2 represents the on / off control of the LED backlight, and number 3 represents the signal waveform of V sync or TE. A method for reducing backlight power consumption in this embodiment includes controlling signal output according to TFT Timing parameters. The TFT Timing parameters include V front porch, V back porch, V sync pulse, and V display active, where the sum of V front porch, V back porch, and V sync pulse is V Blanking. Based on the displayed V blanking and V display, the backlight is controlled to be turned off in the V blanking area, including a TE mode (TE is the abbreviation of Tearing Effect, which represents a signal output by the screen driver IC and is synchronized with the frame rate). In TE mode, the LCD turns on TE output and TE is connected to the dimming control pin of the LED driver circuit.

[0029] When using TE mode, the software setting turns on TE. When the LED Driver dimming control pin receives the TE trigger signal, the LED backlight is turned off. When TE is restored, the LED dimming is synchronously restored to the original state.

[0030] The backlight is off during the V Blanking period and on during the V Display Active period. The backlight power saving ratio of a frame is the ratio of V Blanking to the entire frame. The V Blanking area is the transition period when the TFT switches from one frame to another. During this area, the source signal does not output a valid signal to the TFT. This period is a no-output state and the screen is black. There is output only during the V Display Active period.

[0031] The implementation principle of this embodiment is as follows: the V blanking region is the transition period when the TFT switches from one frame to another. During this region, the source signal does not output a valid signal to the TFT. This period is a no-output state, and the screen is black. Output is only present during the V display active period. At this time, the backlight is controlled to be off during the V blanking period and on during the V display active period. The backlight power saving ratio of a frame is the ratio of V blanking to the entire frame. Due to the timing setting, the backlight is synchronously controlled to turn on and off via the TE signal in the V blanking region. At the same time, because the backlight is turned off in the blanking region, the black screen is darker, thereby improving contrast.

[0032] Example 2

[0033] Combine Figure 1-2 This embodiment is further improved on the basis of the first embodiment in that it also includes a V sync signal mode. In the V sync signal mode, the V sync signal is connected to the dimming control pin of the LED Driver circuit at the system end.

[0034] In the V Blanking region, the backlight switch is synchronously controlled by the V Sync signal or the TE signal. BL on indicates turning on the backlight, and BL off indicates turning off the backlight. BL is the abbreviation for backlight. BL off is set based on the V blanking time. Energy saving is achieved based on the ratio of BL off time to (BL on + BL off) time. The formula is as follows:

[0035] Energy saving ratio = .

[0036] The implementation principle of this embodiment is: the BL switch is controlled according to the display blanking and display, and synchronized by the V sync or TE signal, so as to achieve precise control of the backlight without affecting the display performance, and achieve higher energy saving.

[0037] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A method for reducing backlight power consumption, comprising controlling signal output according to TFT Timing parameters, characterized in that: According to the displayed V blanking and V display conditions, the backlight is controlled to be turned off in the V blanking area, and there are two modes: TE mode and V sync signal mode. In TE mode, the LCD turns on the TE output and connects TE to the dimming control pin of the LED driver circuit. In the V sync signal mode, the V sync signal is connected to the dimming control pin of the LED Driver circuit at the system end; When using TE mode, the software is set to turn on TE. When the LED Driver dimming control pin receives a TE trigger signal, the LED backlight is turned off. When TE is restored, the LED dimming is synchronously restored to its original state. When using V sync signal, when the LED Driver dimming control pin receives a V sync trigger signal, the LED backlight is turned off. When V sync is restored, the LED dimming is synchronously restored to its original state. In the V Blanking region, the backlight switch is synchronously controlled by the V Sync signal or the TE signal. BL on indicates turning on the backlight, and BL off indicates turning off the backlight. BL off is set according to the V blanking time, and energy saving is achieved according to the ratio of BL off to (BL on + BL off). The formula is as follows: Energy saving ratio = ; The backlight is turned off during the V Blanking period and turned on during the V display active period, and the backlight power saving ratio of a frame is the ratio of V blanking to the entire frame.

2. The method for reducing backlight power consumption according to claim 1, wherein: The TFT Timing parameters include V front porch, V back porch, V sync pulse, and V display active, wherein the sum of V front porch, V back porch, and V sync pulse equals V Blanking.

Images