WO2019080307A1

WO2019080307A1 - Display system and current driving method

Info

Publication number: WO2019080307A1
Application number: PCT/CN2017/116295
Authority: WO
Inventors: 单剑锋
Original assignee: 惠科股份有限公司
Priority date: 2017-10-26
Filing date: 2017-12-14
Publication date: 2019-05-02
Also published as: CN107818764A

Abstract

A display system and a current driving method. The current driving method comprises: sensing an operating temperature corresponding to at least one light emitting source, and converting the operating temperature into a numerical reference value, the numerical reference value corresponding to a predetermined driving current of the at least one light emitting source; converting the numerical reference value into a first electrical parameter; measuring a second electrical parameter corresponding to an operating driving current of the at least one light emitting source; comparing the first electrical parameter with the second electrical parameter, and generating a driving bias current according to the comparison result; and adjusting the operating driving current of the at least one light emitting source according to the driving bias current.

Description

Title of Invention: Display System and Current Drive Method

Technical field

[0001] The present application relates to the field of liquid crystal display technology, and in particular, to a display system and a current driving method.

Background technique

[0002] In general, liquid crystal display (LCD) components are used in a variety of applications, such as notebook computers, mobile phones, personal digital assistants, car dashboards, and the like. Typically, the illuminating source is located in the LCD module, such as behind a liquid crystal layer, to facilitate viewing of the image and to produce an optimum illuminating effect. The illuminating light source can be a fluorescent lamp, an electroluminescent component, a light emitting diode (LED), a gaseous discharge lamp, or the like. The general control circuit provides a rectified current to the illuminating source.

As shown in FIG. 1, the illuminating light source module 104 can be located behind a light modulator in the LCD assembly. The illuminating light source module 104 includes a series of light emitting diodes (LEDs). An LED current control integrated circuit (also referred to as a controller) 102 controls the drive current of the light source module 104. The output DRV of the controller 102 is coupled to the base of the transistor 108 via an RC filter 106. The collector of transistor 108 is coupled to power supply unit Vcc via connector load resistor 110. The emitter of transistor 108 is grounded. The collector of transistor 108 is further coupled to illuminating light source module 104 via diode 112. The output of the illuminating light source module 104 is grounded via a bias resistor 114. The output of the light source module 104 is also coupled to the terminal FB of the controller 102. Capacitor 116 grounds power supply unit Vcc. Another capacitor 118 grounds diode 112.

In another conventional current regulator 100, the bias resistor 114 determines a drive current value that can flow through the illuminating light source module 104. Controller 102 outputs a fixed enable signal to the base of transistor 108 via RC filter 106. Transistor 108 provides a predetermined drive current to illuminating light source module 104. Typically, once the resistance value of the bias resistor 114 is established, the drive current through the illumination source module 104 cannot be adjusted. The LED brightness of the illuminating light source module 104 is proportional to the driving current flowing through the illuminating light source module 104. Long-term use of the circuit components may cause unpredictable changes in the drive current of the illuminating light source module 104. In addition, drive currents in certain types of LEDs, such as organic LEDs (OLEDs), may change due to changes in the operating temperature of current regulator 100. As a result, the brightness of the LEDs within the illuminating light source module 104 may be detrimental. Therefore, there is a need for a method and apparatus for controlling the drive current of an illumination source module within an LCD system. technical problem

In view of the above problems in the prior art, the present application provides a display system and a current driving method for controlling a working drive current of an illuminating light source in a liquid crystal display system according to different usage conditions.

Problem solution

Technical solution

[0006] In one aspect, the embodiment of the present application provides a display system, including: a display device having at least one illuminating light source; and a current controller connected to the at least one illuminating light source, the current controller comprising: a meter Calculating a total lighting time of the at least one illuminating light source; the storage device is connected to the meter, configured to store a plurality of digital reference values respectively corresponding to different total lighting ticks, wherein each digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; a digital-to-analog converter connected to the storage device and a digital reference value for converting the total lighting time of the at least one illuminating light source into a first electrical parameter; a comparator, a connection And the digital-to-analog converter is configured to compare the first electrical parameter with a second electrical parameter corresponding to a working drive current of the at least one illuminating light source, and generate a driving bias current; and a current regulator to connect the comparison And adjusting a working drive current of the at least one illuminating light source according to the driving bias current, wherein the driving bias current corresponds to the The difference between the first electrical parameter and the second electrical parameter.

On the other hand, an embodiment of the present application provides a current driving method for a display system, including: calculating a meter corresponding to a total lighting time of the at least one light source, and converting the at least one light The total lighting time of the light source is a digital reference value, wherein the digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; converting the digital reference value into a first electrical parameter; and measuring the work corresponding to the at least one illuminating light source a second electrical parameter of the driving current; comparing the first electrical parameter with the second electrical parameter, and generating a driving bias current according to the comparison result; and adjusting the operation of the at least one illuminating light source according to the driving bias current Drive current.

In another aspect, an embodiment of the present disclosure provides a display system, including: a display device having at least one illuminating light source; and a current controller connecting the at least one illuminating light source, wherein the current controller comprises: an environment a light sensor that senses ambient brightness in front of the display device; a storage device coupled to the ambient light sensor, configured to store a plurality of digital reference values respectively corresponding to different ambient brightness, wherein each digital reference value Corresponding to a predetermined driving current of the at least one illuminating light source; a digital-to-analog converter connected to the storage device and a digital reference value for converting ambient brightness in front of the display device into a first An electrical parameter; a comparator connected to the digital-to-analog converter and configured to compare the first electrical parameter with a second electrical parameter corresponding to a working drive current of the at least one illuminating light source, and generate a driving bias current; a regulator, connecting the comparator and adjusting a working drive current of the at least one illuminating light source according to the driving bias current, wherein the driving bias current corresponds to the first electrical parameter and the second electrical parameter The difference between the two.

In another aspect, an embodiment of the present application provides a current driving method for a display system, including: calculating an ambient light sensor corresponding to an ambient brightness in front of a display device, and converting the ambient brightness to a digital reference value, The digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; converting the digital reference value into a first electrical parameter; measuring a second electrical parameter corresponding to the working driving current of the at least one illuminating light source; comparing the first An electrical parameter and the second electrical parameter, and generating a driving bias current according to the comparison result; and adjusting a working driving current of the at least one illuminating light source according to the driving bias current.

[0010] In another aspect, an embodiment of the present application provides a display system, including: a display device having at least one illuminating light source; and a current controller connecting the at least one illuminating light source, wherein the current controller includes

a working temperature sensor sensing an operating temperature of the at least one illuminating light source; a storage device coupled to the operating temperature sensor, configured to store a plurality of digital reference values respectively corresponding to different operating temperatures, wherein each The digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; the digital-to-analog converter is connected to the storage device and a digital reference value for converting the operating temperature of the at least one illuminating light source into a first electrical parameter; a comparator connected to the digital-to-analog converter and configured to compare the first electrical parameter with a second electrical parameter corresponding to a working drive current of the at least one illuminating light source, and generate a driving bias current; and a current regulator, Connecting the comparator and adjusting a working drive current of the at least one illuminating light source according to the driving bias current, wherein the driving bias current corresponds to a difference between the first electrical parameter and the second electrical parameter value.

[0011] In another aspect, an embodiment of the present application provides a current driving method for a display system, including: calculating a working temperature sensor corresponding to an operating temperature of the at least one illuminating light source, and converting the working temperature to a number a reference value, wherein the digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; converting the digital reference value into a first electrical parameter; measuring a second electrical parameter corresponding to the working driving current of the at least one illuminating light source; a first electrical parameter and a second electrical parameter, and generating a driving bias current according to the comparison result; and adjusting a working driving current of the at least one illuminating light source according to the driving bias current. [0012] In another aspect, an embodiment of the present application provides a display system, including: a display device having at least one illuminating light source; and a current controller connecting the at least one illuminating light source, the current controller comprising: a light sensor that senses an ambient brightness in front of the display device; a working temperature sensor that senses an operating temperature of the at least one light source; a storage device that connects the ambient light sensor and the operating temperature The sensor is configured to store a plurality of digital reference values respectively corresponding to different ambient brightnesses and different operating temperatures, wherein each digital reference value corresponds to a predetermined driving current of the at least one light source; the digital to analog converter is connected to the The storage device and the digital reference value for converting the ambient brightness in front of the display device and the operating temperature of the at least one illuminating light source into a first electrical parameter; a comparator connected to the digital-to-analog converter and used for comparing Determining a first electrical parameter and a second electrical parameter corresponding to a working drive current of the at least one illuminating light source, and generating a driving bias And a current regulator connected to the comparator and adjusting a working drive current of the at least one illuminating light source according to the driving bias current, wherein the driving bias current corresponds to the first electrical parameter and the second The difference between the electrical parameters.

[0013] In another aspect, an embodiment of the present application provides a display system, including: a display device having at least one illuminating light source; and a current controller connecting the at least one illuminating light source, the current controller comprising: a storage device configured to store a plurality of first digital reference values respectively corresponding to different usage conditions, wherein each first digital reference value corresponds to a predetermined driving current of the at least one illuminating light source; a first digital to analog converter, connected The first storage device and the first digital reference value for converting the use condition into a first electrical parameter; the light sensor sensing the brightness of the at least one light source; the second storage device, connecting the a photo sensor, configured to store a second digital reference value, wherein the second digital reference value corresponds to a working drive current of the at least one illuminating light source; and a second digital to analog converter coupled to the second storage device And converting the second digital reference value into a second electrical parameter; a comparator connected to the first digital to analog converter and the second digital to analog And a converter for comparing the first electrical parameter with the second electrical parameter and generating a driving bias current; and a current regulator connecting the comparator and adjusting the at least one illumination according to the driving bias current a working drive current of the light source, wherein the drive bias current corresponds to a difference between the first electrical parameter and the second electrical parameter.

[0014] In another aspect, an embodiment of the present application provides a current driving method for a display system, including: converting a first digital reference value into a first electrical parameter, wherein the first digital reference value corresponds to at least one illuminating light source Determining a driving current; sensing a photo sensor corresponding to the brightness of the at least one illuminating light source, and converting the The brightness of the at least one illuminating light source is a second digital reference value, wherein the second digital reference value corresponds to a working driving current of the at least one illuminating light source; converting the second digital reference value into a second electrical parameter; comparing the first An electrical parameter and the second electrical parameter, and generating a driving bias current according to the comparison result; and adjusting a working driving current of the at least one illuminating light source according to the driving bias current.

Advantageous effects of the invention

Beneficial effect

[0015] Based on the above, the present application pre-stores a plurality of digital reference values by the storage device, so that each digital reference value corresponds to different usage conditions, and selects a corresponding digital reference value as the adjusted working drive current according to different usage conditions. in accordance with. In addition, the second electrical parameter of the present application, in addition to the direct measurement of the driving current, can also be achieved by directly setting the light sensor to obtain the corresponding working drive current to avoid the same current. The brightness difference caused by the total lighting temperature or the different working temperatures. Brief description of the drawing

DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are some embodiments of the present application. Other drawings may also be obtained from those of ordinary skill in the art in view of the drawings.

1 is a schematic diagram of a conventional current regulator for an illuminating light source.

2 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a voltage comparator according to an embodiment of the present application.

3 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a current comparator according to an embodiment of the present application.

[0020] FIG. 4 is a flow chart showing the steps of adjusting the working drive current flowing through the illuminating light source in the embodiment of the present application.

[0021] FIG. 5 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a voltage comparator according to another embodiment of the present application.

6 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a current comparator according to another embodiment of the present application.

7 is a flow chart showing the steps of adjusting the working drive current flowing through the illuminating light source in another embodiment of the present application. 8 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a voltage comparator according to another embodiment of the present application.

9 is a schematic diagram of a controller for providing a light source to adjust a working drive current by using a current comparator according to another embodiment of the present application.

10 is a flow chart showing the steps of adjusting the working drive current flowing through the illuminating light source in another embodiment of the present application.

[0027] FIG. 11 is a schematic diagram of a controller for providing a light source to adjust a working drive current using a voltage comparator according to another embodiment of the present application.

12 is a schematic diagram of a controller for providing a light source to adjust a working drive current using a current comparator according to another embodiment of the present application.

[0029] FIG. 13 is a flow chart showing the steps of adjusting the working drive current flowing through the illuminating light source in another embodiment of the present application.

Embodiments of the invention

[0030] The technical solutions in the embodiments of the present application are clearly and completely described in the following with reference to the accompanying drawings in the embodiments. It is apparent that the described embodiments are part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application, without departing from the inventive work, are within the scope of the present application.

Referring to FIG. 2, a display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and at least one illuminating light source 214 can include a plurality of series connected L. ED 242 (l)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the illumination source 214 may include a backlight source for the LCD system, for example LED backlight sources for small LCD systems, LED backlight sources can include a variety of LEDs, such as white LEDs, color LEDs and organic LEDs (OLEDs). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: a counter 221, a storage device 220, a digital to analog converter 222, a comparator 235, and a current regulator 212. The meter 221 calculates the total lighting time of the at least one illuminating light source 214. For example, the calculation of the total lighting time can be initiated by the meter 221 by the driving signal DRV. The storage device 220, the connection meter 221, is configured to store a plurality of digital reference values 226 respectively corresponding to different total lighting turns, wherein each digital reference value 226 corresponds to a predetermined driving current of the at least one illuminating light source 214, the digital reference The value can be derived from the desired operating conditions of the simulated illumination source 214. If the brightness of the illuminating light source 214 and the illuminating light The drive current of the source 214 is proportional, and the preferred drive current value corresponding to the desired brightness of the illuminating source 214 can be derived from the operating conditions of the desired brightness of the illuminating source 214, and then the preferred drive current value can be utilized with an analog to digital converter. Converted into a digital reference value and stored in the storage device 220, since the illuminable component will have a light decay phenomenon depending on the total lighting time, that is, the total lighting time between 100 hours and the total lighting time is 5000 hours. The illuminating light source emits different brightness under the same working drive current. Generally, the brightness of the total illuminating time of 500 吋 is less than the brightness of 100 吋 between the total lighting times. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be proportional to the total lighting time of the illuminating light source 214, that is, the longer the total lighting time of the illuminating light source 214 is, the larger the predetermined driving current is. Increase the working drive current to compensate for the light decay phenomenon. The digital-to-analog converter 222 is connected to the storage device 220 and the digital reference value 226 for converting the total lighting time of the at least one illuminating light source 214 into a first electrical parameter. For example, the digital-to-analog converter 222 first sets the digital reference value 226. Converting to an analog signal and transferring the analog signal to a voltage reference unit 230, the voltage reference unit 230 is configured to generate a reference voltage signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the voltage reference unit 230 is shown as independent. The unit, however, voltage reference unit 230 can be combined into a digital to analog converter 2 22, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 235 is a voltage comparator 235, and is electrically connected to the digital-to-analog converter 222 through the voltage reference unit 230, and is configured to compare the first electrical parameter (eg, the reference voltage value) with the second working operating current of the corresponding illuminating source 214. Electrical parameters (eg, feedback voltage values), and generate a drive signal DRV corresponding to the difference between the two input voltages (eg, drive bias current), and the current regulator 212 is coupled to the comparator 235 and adjusts at least one illumination according to the drive bias current The operating current of the light source 214, in the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240 for adjusting the operating drive current of the light source 214, the gate terminal and the voltage of the MOS transistor 240. The comparator 235 is connected, and receives the driving signal DRV, and the source terminal of the MOS transistor 240 is grounded. The drain terminal of the MOS transistor 240 is further connected to the illuminating light source 214 via the diode D. The diode D is also grounded via the bypass capacitor C, and the diode D is used for protection. The illuminating light source 214 prevents the controller 260 from malfunctioning, and is used to drain the undesired high frequency current through the bypass capacitor C. Application, the current controller further comprises a detector 216, detector 216 connected to light source 214 and to measure a second electrical parameter (eg: a feedback voltage value). The detector 216 is coupled to the illumination source 214, and the detector 216 includes a detector resistor Rs for determining a corresponding operational drive through the illumination source 214. The voltage FB of the moving current, the detector resistor Rs is connected to the input of the voltage comparator 235, and the voltage comparator 25 receives the voltage FB and will be compared with the first electrical parameter (eg: reference voltage value) from the voltage reference unit 230. And generating a driving signal DRV of the gate terminal of the MOS transistor 240. The driving signal DRV drives the gate terminal of the MOS transistor 240 according to the difference between the voltage F _B and the reference voltage value, and the MOS transistor 240 adjusts the light source 214 according to the driving signal DRV. The working drive current, for example, the total lighting time of the illuminating light source 214 is 5000 吋, the predetermined driving current is 5 A, and the first electrical parameter (reference voltage value) is 120 V, but the illuminating light source is too long due to lighting When the working drive current of 214 is reduced to 3A and the second electrical parameter (voltage FB) is 100V, the difference between the voltage FB and the reference voltage value generates a relatively strong driving signal DRV, resulting in a working driving current of the illuminating light source 214. Increasing, in the same way, if the working drive current flowing through the illuminating light source 214 is too large, the voltage comparator 235 generates a relatively weak driving signal DRV, causing the illuminating light source 214 to work. Drive current is reduced.

[0033] Therefore, the meter 221 can be set in the current controller 260 to calculate the total lighting time, the current controller 26

0 automatically selects the corresponding digital reference value 226 according to the total lighting time, and accordingly increases the working drive current to compensate for the light decay phenomenon.

Referring to FIG. 3, the display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and the at least one illuminating light source 214 can include a plurality of series connected L. ED 242 (l)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the light source 214 may include a backlight source for the LCD system. For example, LED backlight sources for small LCD systems, LED backlight sources can include various LEDs, such as white LEDs, color LEDs, and organic LEDs (OLEDs). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: a meter 221, a storage device 220, a digital to analog converter 222, a comparator 235, and a current regulator 212. The meter 221 calculates the total lighting time of the at least one illuminating light source 214. For example, the calculation of the total lighting time can be initiated by the meter 221 by the driving signal DRV. The storage device 220, the connection meter 221, is configured to store a plurality of digital reference values 226 respectively corresponding to different total lighting turns, wherein each digital reference value 226 corresponds to a predetermined driving current of the at least one illuminating light source 214, the digital reference The value can be derived from the desired operating conditions of the simulated illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then Preferred drive current value In order to convert the digital converter into a digital reference value and store it in the storage device 220, since the illuminable component will have a light fading phenomenon depending on the total lighting time, that is, the total lighting time is 100 吋 and total The illuminating light source that illuminates 5000 吋 between turns is different in brightness at the same working drive current. Generally, the brightness of 5000 吋 between the total lighting times is less than the brightness of 100 吋 between the total lighting times. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be proportional to the total lighting time of the illuminating light source 214, that is, the longer the total lighting time of the illuminating light source 214 is, the larger the predetermined driving current is, Increase the working drive current to compensate for the light decay phenomenon. The digital-to-analog converter 222 is connected to the storage device 220 and the digital reference value 226 for converting the total lighting time of the at least one illuminating light source 214 into a first electrical parameter. For example, the digital-to-analog converter 222 first sets the digital reference value. 226 converts to an analog signal and converts the analog signal to a current reference unit 232. The current reference unit 232 is configured to generate a reference current signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the current reference unit 232 is shown as independent. The units, however, current reference unit 232 can be combined into a digital to analog converter 222, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 237 is a current comparator 237, and is electrically connected to the digital-to-analog converter 222 through the current reference unit 232, and is configured to compare the first electrical parameter (eg, the reference current value) with the second working operating current of the corresponding illuminating source 214. Electrical parameters (such as: feedback current value), and generate a driving signal D RV corresponding to the difference between the two input currents (such as: driving bias current), and the current regulator 212 is connected to the comparator 235 and adjusted according to the driving bias current at least one In the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240 for adjusting the operating drive current of the light source 214, and the gate terminal of the MOS transistor 240 is The current comparator 237 is connected, and receives the driving signal DRV, and the source terminal of the MOS transistor 240 is grounded. The drain terminal of the MOS transistor 240 is further connected to the light source 214 via the diode D. The diode D is also grounded via the bypass capacitor C, and the diode D is used. The illuminating light source 214 protects the controller 260 from malfunction and is drained through the bypass capacitor C with an undesired high frequency current.

In a particular application, the current controller further includes a detector 216 coupled to the illumination source 214 and configured to measure a second electrical parameter (eg, a feedback current value). The detector 216 is coupled to the illumination source 214, and the detector 216 includes a sense resistor Rs and a pair of MOS transistors 252a and 252b. The gate terminals of the MOS transistors 252a and 252b are grounded, and the drain terminal of the MOS transistor 252b is connected to the gate terminal. The drain terminal of the MOS transistor 252a is connected to the current comparator 237, and when the drive current flowing through the light source 214 is changed, the detector resistance R The voltage FB across the s will also change, and the change in voltage FB causes the gate bias of MOS transistors 252a and 252b to change, causing the current flowing through the drain terminal of MOS transistor 252a to change, when current comparator 2 37 detects After the current flowing through the MOS transistor 252b is different from the reference current value, the current comparator 237 generates a driving signal DRV corresponding to the difference, and the driving signal DRV adjusts the driving current of the current regulator 212, for example, the light source 214. The total lighting time is 5000 hours, the predetermined driving current is 5A, and the first electrical parameter (reference current value) is 5A. However, due to the long time between lighting, the working drive current of the light source 214 is reduced to 3A. The second electrical parameter is 3A, and the difference between the current and the reference current value produces a relatively strong driving signal DRV, causing the working drive current of the illuminating source 214 to increase. Similarly, if the working driving current flows through the illuminating source 214. If it is too large, the current comparator 237 generates a relatively weak drive signal DRV, causing the operating drive current of the illuminating light source 214 to decrease.

[0036] Therefore, the meter 221 can be set in the current controller 260 to calculate the total lighting time, and the current controller 26 0 automatically selects the corresponding digital reference value 226 according to the total lighting time, and accordingly increases the work. Drive current to compensate for light decay.

Referring to FIG. 4, in this embodiment, the steps are performed in a specific order. However, if the circuit is executed in an appropriate circuit, the above steps may be performed in any specific order, and may be performed in any order or sequentially. First, in step 410, a meter corresponding to the total lighting time of the illuminating light source is calculated, and the total lighting time of the illuminating light source is converted to a digital reference value, wherein the digital reference value corresponds to a predetermined driving current of the illuminating light source. Step 420, then converting the digital reference value to a first electrical parameter (voltage or current). Step 430: Measure a second electrical parameter (voltage or current) corresponding to the working drive current of the illuminating light source. Step 440, comparing the first electrical parameter with the second electrical parameter. Next, in step 450, it is determined whether there is a difference between the measured first electrical parameter and the second electrical parameter. If there is a difference, step 460 is executed to generate a driving bias current according to the comparison result to adjust the working driving current of the illuminating light source, and steps 430 to 460 are repeatedly performed until there is no difference between the first electrical parameter and the second electrical parameter. , then it ends.

Referring to FIG. 5, the display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and the at least one illuminating light source 214 can include a plurality of series connected devices. LED 242 (l)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the light source 214 may include a backlight source for the LCD system. For example, LED backlight sources for small LCD systems, LED backlight sources can include various LEDs, such as white LEDs, color LED and organic LED (OLED). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: an ambient light sensor 223, a storage device 220, a digital to analog converter 222, a comparator 235, and a current regulator 212. The ambient light sensor 223 senses the ambient brightness in front of the display device. The storage device 220 is connected to the ambient light sensor 223, and configured to store a plurality of digital reference values 226 corresponding to different ambient brightnesses, wherein each of the digital reference values 226 corresponds to a predetermined driving current of the at least one light source 214, and the digital reference value It can be derived from the operating conditions required to simulate the illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then The preferred driving current value can be converted into a digital reference value by using an analog-to-digital converter and stored in the storage device 220. Since the human eye needs a relatively high backlight in a relatively bright environment, the content on the display device can be clearly seen. In a darker environment, too high a backlight can cause discomfort or even damage to the eyes, which in turn requires lower backlighting. The digital reference 226 performs different degrees of control of the working drive current for different ambient brightness. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be proportional to the ambient brightness, that is, the brighter the ambient brightness, the larger the predetermined driving current is to increase the working driving current to generate a higher backlight. The digital-to-analog converter 222 is connected to the storage device 220 and the digital reference value 226 for converting the ambient brightness in front of the display device into a first electrical parameter. For example, the digital-to-analog converter 222 first converts the digital reference value 226 into an analog signal and The analog signal is forwarded to a voltage reference unit 230, and the voltage reference unit 230 is configured to generate a reference voltage signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the voltage reference unit 230 is displayed as a separate unit, however, the voltage Reference unit 230 can be combined into a digital to analog converter 222, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 235 is a voltage comparator 235, and is electrically connected to the digital-to-analog converter 222 through the voltage reference unit 230, and is configured to compare the first electrical parameter (eg, the reference voltage value) with the second working operating current of the corresponding illuminating source 214. Electrical parameters (eg, feedback voltage values), and generate a drive signal DRV corresponding to the difference between the two input voltages (eg, drive bias current), and the current regulator 212 is coupled to the comparator 235 and adjusts at least one illumination according to the drive bias current The operating current of the light source 214, in the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240 for adjusting the operating drive current of the light source 214, the gate terminal and the voltage of the MOS transistor 240. The comparator 235 is connected and receives the drive signal DRV, and the source terminal of the MOS transistor 240 is grounded, and the drain terminal of the MOS transistor 240 is further The illuminating light source 214 is connected via a diode D. The diode D is also grounded via a bypass capacitor C. The diode D is used to protect the illuminating source 214 from failure of the controller 260 and to drain the undesired high frequency current through the bypass capacitor C.

[0039] In a particular application, the current controller further includes a detector 216 coupled to the illumination source 214 and configured to measure a second electrical parameter (eg, a feedback voltage value). The detector 216 is connected to the illuminating light source 214. The detector 216 includes a detector resistor Rs for measuring the voltage FB corresponding to the working driving current flowing through the illuminating source 214, the detector resistor Rs and the voltage comparator 235. An input is connected, the voltage comparator 235 receives the voltage FB and will compare with a first electrical parameter (eg, a reference voltage value) from the voltage reference unit 230, and generate a drive signal DRV of the gate terminal of the MOS transistor 240, the drive signal The DRV drives the gate terminal of the MOS transistor 240 according to the difference between the voltage FB and the reference voltage value, and the MOS transistor 240 adjusts the working driving current of the illuminating light source 214 according to the driving signal DRV, for example, the ambient brightness in front of the display device is 200 nits, then predetermined The driving current is 5A, and the first electrical parameter (reference voltage value) is 120V, but the working driving current of the xenon light source 214 is only 3A, and the second electrical parameter (voltage FB) is 100V, then the voltage FB and the reference voltage value are The difference between the two produces a relatively strong drive signal DRV, resulting in a working drive current of the illuminating source 214. Was added to produce a higher backlight, the same token, if the current flowing through the light emitting operation of the drive source 214 is too large, the voltage comparator 235 generates a drive signal DRV is relatively weak, causing a light emitting operation of the drive current source 214 is reduced.

[0040] Therefore, the ambient light sensor 223 can be disposed in the current controller 260 to sense the ambient brightness in front of the display device, and the current controller 260 automatically selects a corresponding digital reference value 226 according to the ambient brightness, and adjusts the work drive accordingly. Current.

Referring to FIG. 6, the display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and the at least one illuminating light source 214 can include a plurality of serial connections. LED 242 (l)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the illumination source 214 may include a backlight source for the LCD system, for example LED backlight source for small LC D system, LED backlight source can include various LEDs, such as white LED, color LED and organic LED (OLED). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: an ambient light sensor 223, a storage device 220, a digital to analog converter 222, a comparator 235, and a current regulator 212. The ambient light sensor 223 senses the ambient brightness in front of the display device. The storage device 220 is connected to the ambient light sensor 223, and configured to store a plurality of digital reference values 226 corresponding to different ambient brightnesses, wherein each of the digital reference values 226 corresponds to a predetermined driving current of the at least one light source 214, and the digital reference value It can be derived from the operating conditions required to simulate the illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then The preferred driving current value can be converted into a digital reference value by using an analog-to-digital converter and stored in the storage device 220. Since the human eye needs a relatively high backlight in a relatively bright environment, the content on the display device can be clearly seen. In a darker environment, too high a backlight can cause discomfort or even damage to the eyes, which in turn requires lower backlighting. The digital reference 226 performs different degrees of control of the working drive current for different ambient brightness. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be proportional to the ambient brightness, that is, the brighter the ambient brightness, the larger the predetermined driving current is to increase the working driving current to generate a higher backlight. The digital-to-analog converter 222 is connected to the storage device 220 and the digital reference value 226 for converting the ambient brightness in front of the display device into a first electrical parameter. For example, the digital-to-analog converter 222 first converts the digital reference value 226 into an analog signal and The analog signal is forwarded to the current reference unit 232, and the current reference unit 232 is configured to generate a reference current signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the current reference unit 232 is shown as a separate unit, however, the current reference Unit 232 can be combined into a digital to analog converter 222, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 237 is a current comparator 237, and is electrically connected to the digital-to-analog converter 222 through the current reference unit 232, and is configured to compare the first electrical parameter (eg, the reference current value) with the second working operating current of the corresponding illuminating source 214. Electrical parameters (such as: feedback current value), and generate a drive signal DRV corresponding to the difference between the two input currents (such as: drive bias current), and the current regulator 212 is connected to the comparator 235 and adjusts at least one illumination according to the drive bias current The operating current of the light source 214, in the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240 for adjusting the operating drive current of the light source 214, the gate terminal and current of the MOS transistor 240. The comparator 237 is connected and receives the driving signal DRV, and the source terminal of the MOS transistor 240 is grounded. The drain terminal of the MOS transistor 240 is further connected to the illuminating light source 214 via the diode D. The diode D is also grounded via the bypass capacitor C, and the diode D is used for protection. The illuminating source 214 prevents the controller 260 from malfunctioning and is drained through the bypass capacitor C with an undesired high frequency current. [0042] In a specific application, the current controller further includes a detector 216 coupled to the illumination source 214 and configured to measure a second electrical parameter (eg, a feedback current value). The detector 216 is coupled to the illumination source 214. The detector 216 includes a sense resistor Rs and a pair of MOS transistors 252a and 252b. The gate terminals of the MOS transistors 252a and 252b are grounded, and the drain terminal of the MOS transistor 252b is connected to the gate terminal. The drain terminal of the MOS transistor 252a is connected to the current comparator 237. When the driving current flowing through the illuminating light source 214 is changed, the voltage FB across the detector resistor Rs is also changed, and the change of the voltage FB causes the MOS transistor 252a and The gate bias of 252b is changed such that the current flowing through the drain terminal of MOS transistor 252a changes. When current comparator 237 detects that the current flowing through MOS transistor 252b is different from the reference current value, current comparator 23 7 is generated. A drive signal DRV corresponding to the difference, the drive signal DRV adjusts the drive current of the current regulator 212. For example, if the ambient brightness in front of the display device is 200 nits, the predetermined drive current is 5 A, and the first electrical parameter (reference current value) 5A, but the working driving current of the illuminating light source 214 is only 3A, and the second electrical parameter is 3A, the difference between the current and the reference current value generates a relatively strong driving signal DRV, resulting in the operation of the illuminating light source 214. The drive current is increased to produce a higher backlight. Similarly, if the operating drive current flowing through the illuminating source 214 is too large, the current comparator 237 generates equivalent Driving signal DR V, causing the work light source driving current 214 is reduced.

[0043] Therefore, the ambient light sensor 223 can be disposed in the current controller 260 to sense the ambient brightness in front of the display device, and the current controller 260 automatically selects the corresponding digital reference value 226 according to the ambient brightness, and adjusts the work accordingly. Drive current.

Referring to FIG. 7, in this embodiment, the steps are performed in a specific order. However, if the 电路 is performed by an appropriate circuit, the above steps may be performed in any specific order, and may be performed in any order or in sequence. First, in step 411, an ambient light sensor corresponding to the ambient brightness in front of the display device is sensed, and the ambient brightness is converted into a digital reference value, wherein the digital reference value corresponds to a predetermined driving current of the light source. Step 421, then converting the digital reference value to a first electrical parameter (voltage or current). Step 431: Measure a second electrical parameter (voltage or current) corresponding to the working drive current of the illuminating light source. Step 441: Compare the first electrical parameter with the second electrical parameter. Next, in step 451, it is determined whether there is a difference between the measured first electrical parameter and the second electrical parameter. If there is a difference, step 461 is executed to generate a driving bias current according to the comparison result to adjust the working driving current of the illuminating light source, and steps 431 to 461 are repeatedly performed until there is no difference between the first electrical parameter and the second electrical parameter. , then it ends. Referring to FIG. 8, the display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and the at least one illuminating light source 214 can include a plurality of serially connected LEDs 242 ( L)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the illumination source 214 may include a backlight source for the LCD system, for example LED backlight source for small LCD systems, LED backlight sources can include a variety of LEDs, such as white LEDs, color LEDs and organic LEDs (OLEDs). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: an operating temperature sensor 224, a storage device 220, a digital to analog converter 22, a comparator 235, and a current regulator 212. The operating temperature sensor 224 senses the operating temperature of the illuminating light source 214. The storage device 220 is connected to the operating temperature sensor 224 and configured to store a plurality of digital reference values 226 respectively corresponding to different operating temperatures, wherein each of the digital reference values 226 corresponds to a predetermined driving current of the at least one illuminating source 214, and the digital reference value It can be derived from the operating conditions required to simulate the illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then The preferred driving current value can be converted into a digital reference value by using an analog-to-digital converter and stored in the storage device 220. Since the illuminating light source 214 emits the light source 214 with the same working driving current at different temperatures, there will be different brightness. The higher the operating temperature of the illuminating light source 214, the brighter the brightness, so it is necessary to reduce the working drive current. The digital reference 226 performs different degrees of control of the working drive current for different operating temperatures. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be inversely proportional to the operating temperature, that is, the higher the operating temperature, the smaller the predetermined driving current to reduce the operating driving current. The digital-to-analog converter 222 is connected to the storage device 220 and the digital reference value 226 for converting the operating temperature of the illuminating light source 214 into a first electrical parameter. For example, the digital-to-analog converter 222 first converts the digital reference value 226 into an analog signal. And the analog signal is sent to the voltage reference unit 230, and the voltage reference unit 230 is used to generate a reference voltage signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the voltage reference unit 230 is displayed as a separate unit, however, the voltage Reference unit 230 can be combined into a digital to analog converter 222, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 235 is a voltage comparator 235, and is electrically connected to the digital-to-analog converter 22 2 through the voltage reference unit 230, and is configured to compare the first electrical parameter (eg, the reference voltage value) with the working driving current of the corresponding illuminating source 214. Two electrical parameters (such as: feedback voltage value), and generate a drive signal DRV corresponding to the difference between the two input voltages ( For example: driving the bias current), and the current regulator 212 is connected to the comparator 235 and adjusting the working driving current of the at least one illuminating source 214 according to the driving bias current. In the embodiment, the current regulator 212 includes a metal oxide semiconductor ( MOS) transistor 240, MOS transistor 240 is used to adjust the working drive current of the illuminating light source 214, the gate terminal of the MOS transistor 240 is connected to the voltage comparator 235, and receives the driving signal D RV , and the source terminal of the MOS transistor 240 is grounded, the MOS transistor The drain terminal of 240 is further connected to the illuminating light source 214 via a diode D. The diode D is also grounded via a bypass capacitor C. The diode D is used to protect the illuminating source 214 from malfunction of the controller 260, and is used to bypass the unwanted high frequency current. Capacitor C is grounded.

[0046] In a particular application, the current controller further includes a detector 216 coupled to the illumination source 214 and configured to measure a second electrical parameter (eg, a feedback voltage value). The detector 216 is connected to the illuminating light source 214. The detector 216 includes a detector resistor Rs for measuring the voltage FB corresponding to the working driving current flowing through the illuminating source 214, the detector resistor Rs and the voltage comparator 235. The input is connected, the voltage comparator 235 receives the voltage FB and will compare with the first electrical parameter (eg, the reference voltage value) from the voltage reference unit 230, and generate the drive signal DRV of the gate terminal of the MOS transistor 240, the drive signal DRV. The gate terminal of the MOS transistor 240 is driven according to the difference between the voltage FB and the reference voltage value. The MOS transistor 240 adjusts the working driving current of the illuminating light source 214 according to the driving signal DRV. For example, if the operating temperature of the illuminating source 214 is 50 degrees, the predetermined time is predetermined. The driving current is 5A, and the first electrical parameter (reference voltage value) is 120V, but the working driving current of the xenon light source 214 is only 3A, and the second electrical parameter (voltage FB) is 100V, then the voltage FB and the reference voltage value are The difference between the two produces a relatively strong drive signal DRV, causing the operating drive current of the illuminating source 214 to increase. To produce a higher brightness, if the operating drive current flowing through the illuminating source 214 is too large, the voltage comparator 235 generates a relatively weak driving signal DRV, causing the operating drive current of the illuminating source 214 to decrease.

Therefore, the operating temperature sensor 224 can be set in the current controller 260 to sense the operating temperature of the illuminating light source 214, and the current controller 260 automatically selects the corresponding digital reference value 226 according to the operating temperature, and adjusts the working drive accordingly. Current.

Referring to FIG. 9, a display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and at least one illuminating light source 214 can include a plurality of serial connections. LED 242 (l)-(n), LED 242 (l)-(n) can be connected in series, in parallel, or in series and in parallel In an integrated manner, the illuminating light source 214 may include a backlight source for an LCD system, such as an LED backlight source for a small LC D system, and the LED backlight source may include various LEDs such as white LEDs, color LEDs, and organic LEDs (OLEDs). Wait. In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: an operating temperature sensor 224, a storage device 220, a digital to analog converter 222, a comparator 235, and a current regulator 212. The operating temperature sensor 224 senses the operating temperature of the illuminating light source 214. The storage device 220 is connected to the operating temperature sensor 224 and configured to store a plurality of digital reference values 226 respectively corresponding to different operating temperatures, wherein each of the digital reference values 226 corresponds to a predetermined driving current of the at least one illuminating source 214, and the digital reference value It can be derived from the operating conditions required to simulate the illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then The preferred driving current value can be converted into a digital reference value by using an analog-to-digital converter and stored in the storage device 220. Since the illuminating light source 214 emits the light source 214 with the same working driving current at different temperatures, there will be different brightness. The higher the operating temperature of the illuminating light source 214, the brighter the brightness, so it is necessary to reduce the working drive current. The digital reference 226 performs different degrees of control of the working drive current for different operating temperatures. Therefore, the predetermined driving current of the illuminating light source 214 can be set to be inversely proportional to the operating temperature, that is, the higher the operating temperature, the smaller the predetermined driving current to reduce the operating driving current. The digital-to-analog converter 222 is coupled to the storage device 220 and the digital reference value 226 for converting the operating temperature of the illuminating light source 214 into a first electrical parameter. For example, the digital-to-analog converter 222 first converts the digital reference value 226 into an analog signal and The analog signal is forwarded to the current reference unit 232, and the current reference unit 232 is used to generate a reference current signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, the current reference unit 232 is shown as a separate unit, however, the current Reference unit 232 can be combined into a digital to analog converter 222, for example, digital to analog converter 222 can be used to convert digital reference value 226 to a first electrical parameter. The comparator 237 is a current comparator 237, and is electrically connected to the digital-to-analog converter 222 through the current reference unit 232, and is configured to compare the first electrical parameter (eg, the reference current value) with the second working operating current of the corresponding illuminating source 214. Electrical parameters (such as: feedback current value), and generate a drive signal DRV corresponding to the difference between the two input currents (such as: drive bias current), and the current regulator 212 is connected to the comparator 235 and adjusts at least one illumination according to the drive bias current The operating current of the light source 214, in the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240, and the MOS transistor 240 is used to adjust the operating drive of the light source 214. The galvanic current, the gate terminal of the MOS transistor 240 is connected to the current comparator 237, and receives the drive signal DR V , and the source terminal of the MOS transistor 240 is grounded, MOS

The drain terminal of the transistor 240 is further connected to the illuminating light source 214 via a diode D. The diode D is also grounded via a bypass capacitor C. The diode D is used to protect the illuminating light source 214 from the failure of the controller 260, and is used to drain an unwanted high frequency current. The path capacitor C is grounded.

[0049] In a particular application, the current controller further includes a detector 216 coupled to the illumination source 214 and configured to measure a second electrical parameter (eg, a feedback current value). Detector 216 is coupled to illuminating source 214, which includes sense resistor Rs and a pair of MOS transistors 252a and 252b. The gate terminals of the MOS transistors 252a and 252b are grounded, and the drain terminal of the MOS transistor 252b is connected to the gate terminal. The drain terminal of the MOS transistor 252a is connected to the current comparator 237. When the driving current flowing through the illuminating light source 214 is changed, the voltage FB across the detector resistor Rs is also changed, and the change of the voltage FB causes the MOS transistor 252a. The gate bias of 252b is changed such that the current flowing through the drain terminal of MOS transistor 252a changes. When current comparator 237 detects that the current flowing through MOS transistor 252b is different from the reference current value, current comparator 237 is A driving signal DRV corresponding to the difference is generated, and the driving signal DRV adjusts a driving current of the current regulator 212. For example, when the operating temperature of the light source 214 is 50 degrees, the predetermined driving current is 5A, and the first electrical parameter (reference voltage value) ) is 120V, but the working driving current of the illuminating light source 214 is only 3A, and the second electrical parameter (voltage FB) is 100V, the difference between the voltage FB and the reference voltage value generates a relatively strong driving signal DRV, The working drive current of the illuminating light source 214 is increased to generate a higher brightness. Similarly, if the working driving current flows through the illuminating source 214. Is large, the voltage comparator 235 generates a relatively weak drive signal DRV, 214 causing the work light source driving current is reduced.

[0050] Therefore, the operating temperature sensor 224 can be set in the current controller 260 to sense the operating temperature of the illuminating light source 214, and the current controller 260 automatically selects the corresponding digital reference value 226 according to the operating temperature, and adjusts the work accordingly. Drive current.

[0051] In addition, in a specific application, the display system can adjust the working drive current according to the result of the ambient brightness sensing and the working temperature sensing. For example, the display system can include: the ambient light sensor 223 and Operating temperature sensor 224. The ambient light sensor 223 senses the ambient brightness in front of the display device, and the operating temperature sensor 224 senses the operating temperature of the light source 214, and the storage device 220 connects the ambient light sensor 22 and the operating temperature sensor 224. , configured to store different brightness and different operating temperatures for different environments A plurality of digital reference values 226, wherein each digital reference value 226 corresponds to a predetermined drive current of at least one of the illumination sources 214, and the digital reference value can be derived from the desired operating conditions of the simulated illumination source 214. Therefore, the current controller 260 can automatically select a corresponding digital reference value 226 according to the ambient brightness and the operating temperature, and adjust the working drive current accordingly.

Referring to FIG. 10, in the present embodiment, the steps are performed in a specific order. However, if executed in an appropriate circuit, the above steps may be performed in any specific order, and may be performed in any order or sequentially. First, in step 412, a working temperature sensor corresponding to the operating temperature of the illuminating light source is sensed, and the switching operating temperature is a digital reference value, wherein the digital reference value corresponds to a predetermined driving current of the illuminating light source. Step 422, and then converting the digital reference value into a first electrical parameter (voltage or current). Step 432: Measure a second electrical parameter (voltage or current) corresponding to the working drive current of the illuminating light source. Step 442, comparing the first electrical parameter with the second electrical parameter. Next, in step 452, it is determined whether there is a difference between the measured first electrical parameter and the second electrical parameter. If there is a difference, step 462 is performed to generate a driving bias current according to the comparison result to adjust the working driving current of the illuminating light source, and steps 431 to 461 are repeatedly performed until there is no difference between the first electrical parameter and the second electrical parameter. , then it ends.

Referring to FIG. 11, a display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and at least one illuminating light source 214 can include a plurality of serial LEDs. 242 (l)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the light source 214 may include a backlight source for the LCD system, for example For LED backlight sources in small LC D systems, LED backlight sources can include a variety of LEDs, such as white LEDs, color LEDs, and organic LEDs (OLEDs). The current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: a use condition 225, a first storage device 220, a first digital to analog converter 222, a second storage device 253, and a second digital to analog converter 254. The comparator 235, the photo sensor 251, and the current regulator 2 12. The use condition 225 can include sensing the operating temperature of the illuminating light source 214, the total lighting time of the illuminating light source 214, and the ambient brightness in front of the display device. The first storage device 220, the connection use condition 225, is configured to store a plurality of first digital reference values 226 corresponding to different usage conditions 225, each of the first digital reference values 226 corresponding to a predetermined driving current of the at least one illumination source 214, The first digital reference value 226 can be derived from the desired operating conditions of the simulated illumination source 214. If the brightness of the illuminating source 214 is proportional to the driving current flowing through the illuminating source 214, the preferred driving current value corresponding to the desired brightness of the illuminating source 214 can be simulated by The true illumination source 214 is derived from the desired operating conditions of the brightness, and then the preferred drive current value can be converted to a first digital reference value using an analog to digital converter and stored in the first storage device 220, due to different usage conditions 225 The illuminating light source 214 has different brightness, working drive current, etc., so it is necessary to adjust the working drive current of the illuminating light source 214. The first digital reference 226 performs different degrees of control of the working drive current for different usage conditions 2 25 . The first digital-to-analog converter 222 is connected to the first storage device 220 and the first digital reference value 226 for converting the operating temperature of the illuminating light source 214 into a first electrical parameter, for example: the first digital-to-analog converter 222 first A digital reference value 226 is converted into an analog signal and converted to an analog signal to the first voltage reference unit 230. The first voltage reference unit 230 is configured to generate a reference voltage signal (first electrical parameter) corresponding to the analog signal. For the sake of explanation, The first voltage reference unit 230 is shown as a separate unit. However, the first voltage reference unit 230 may be combined into a first digital to analog converter 222. For example, the first digital to analog converter 222 may be configured to use the first digital reference value 226. Converted to the first electrical parameter. In addition, the same, the photo sensor 251 can sense the brightness of the illuminating light source 214. The second storage device 252 is connected to the photo sensor 251 and configured to store a plurality of second digital reference values 253 respectively corresponding to the brightness of the different illumination sources 214, wherein each of the second digital reference values 253 corresponds to the at least one illumination source 214 The operational drive current, the second digital reference 253, can be derived from the desired operating conditions of the simulated illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the operating drive current flowing through the illuminating source 214, the value of the operating drive current corresponding to the brightness of the illuminating source 214 can be derived from the operating conditions of the emulated illuminating source 214, and then the operating drive current value The analog to digital converter can be converted to a digital reference value 253 and stored in the second storage device 252. The second digital-to-analog converter 254 is connected to the second storage device 252 and the second digital reference value 253 for converting the brightness of the illuminating light source 214 into a second electrical parameter. For example, the second digital-to-analog converter 222 first performs the second The digital reference value 253 is converted into an analog signal and converted to an analog signal to the second voltage reference unit 255. The second voltage reference unit 255 is configured to generate a second electrical parameter corresponding to the analog signal. For the sake of explanation, the second voltage reference unit 255 Displayed as separate units, however, the second voltage reference unit 255 can be combined into a second digital to analog converter 254, for example, the second digital to analog converter 254 can be used to convert the second digital reference value 253 into a second electrical parameter. . The comparator 235 is a voltage comparator 235, is electrically connected to the first digital-to-analog converter 222 through the first voltage reference unit 230, and is electrically connected to the second digital-to-analog converter 254 through the second voltage reference unit 255, and is used for comparison. The first electrical parameter (such as: reference voltage value) and the second electrical parameter (such as: feedback voltage value), and generate a driving signal DRV corresponding to the difference between the two input voltages (such as: Driving the bias current), and the current regulator 212 is coupled to the comparator 235 and adjusts the operating drive current of the at least one illuminating source 214 according to the driving bias current. In the present embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS). The transistor 240 and the MOS transistor 240 are used to adjust the operating driving current of the illuminating light source 214. The gate terminal of the MOS transistor 240 is connected to the voltage comparator 235, and receives the driving signal DRV. The source terminal of the MOS transistor 240 is grounded, and the MOS transistor 240 is drained. Extremely further connected to the illuminating source 214 via a diode D, the diode D is also grounded via a bypass capacitor C for protecting the illuminating source 214 from failure of the controller 260 and for undesired high frequency current draining through the bypass capacitor C.

[0054] In a particular application, voltage comparator 235 receives a second electrical parameter (eg, a feedback voltage value) and will compare with a first electrical parameter (eg, a reference voltage value) from first voltage reference unit 230, and The drive signal DRV of the gate terminal of the MOS transistor 240 is generated, the drive signal DRV drives the gate terminal of the MOS transistor 240 according to the difference between the voltage FB and the reference voltage value, and the MOS transistor 240 adjusts the working drive current of the illuminating light source 214 according to the drive signal DRV. For example, the use condition 225 is the ambient brightness in front of the display device. If the ambient brightness in front of the display device is 200 nits, the predetermined drive current is 5 A, and the first electrical parameter (reference voltage value) is 120 V, but the neon sensor 251 senses that the brightness of the illuminating light source 214 is 100 nits, the working current of the brightness of 100 ns is only 3 A, and the second electrical parameter (feedback voltage value) is 100 V, then the difference between the first electrical parameter and the second electrical parameter That is, a relatively strong driving signal _DRV is generated, causing the working driving current of the illuminating light source 214 to increase to generate a higher backlight. Similarly, if the illuminating light source 214 is bright If the corresponding working drive current is too large, the voltage comparator 235 generates a relatively weak drive signal DR V to reduce the operating drive current of the illuminating source 214.

[0055] Therefore, the use condition 225 can be set in the current controller 260, and the current controller 260 automatically selects the corresponding digital reference value 226 according to the use condition 2 25, and does not measure the working drive current of the illumination source 214, but sets The photo sensor 251 directly senses the brightness of the light to avoid a brightness drop caused by the total lighting time or different operating temperatures at the same current, so that the adjustment of the working drive current is more accurate.

Referring to FIG. 12, a display system includes: a display device and a current controller 260. The display device can be a liquid crystal display device having at least one illuminating light source 214, and at least one illuminating light source 214 can include a plurality of serial connections. LED 242 (1)-(n), LED 242 (l)-(n) may be connected in series, in parallel, or in series and in parallel, and the light source 214 may include a backlight source for the LCD system. For small LCD The system's LED backlight source, LED backlight source can include a variety of LEDs, such as white LED, color L ED and organic LED (OLED). In addition, the current controller 260 is connected to at least one illuminating light source 214, and the current controller 260 includes: a use condition 225, a first storage device 220, a first digital to analog converter 222, a second storage device 253, and a second digital to analog conversion. The device 254, the comparator 235, the photo sensor 251 and the current regulator 212. The use condition 225 can include sensing the operating temperature of the illuminating light source 214, the total lighting time of the illuminating light source 214, and the ambient brightness in front of the display device. The first storage device 220, the connection use condition 225, is configured to store a plurality of first digital reference values 226 respectively corresponding to the different use conditions 225, wherein each of the first digital reference values 226 corresponds to a predetermined drive current of the at least one illumination source 214 The first digital reference value can be derived from the desired operating conditions of the simulated illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the drive current flowing through the illuminating source 214, the preferred drive current value corresponding to the desired brightness of the illuminating source 214 may be derived from the operating conditions that simulate the desired brightness of the illuminating source 214, and then The preferred drive current value can be converted to the first digital reference value by the analog to digital converter and stored in the first storage device 220. Since the different illumination conditions 225, the illumination source 214 will have different brightness, working drive current, etc. Therefore, it is necessary to adjust the working drive current of the illuminating light source 214. The first digital reference 226 performs different degrees of control of the working drive current for different usage conditions 225. The first digital-to-analog converter 222 is connected to the first storage device 220 and the first digital reference value 226 for converting the operating temperature of the illuminating light source 214 into a first electrical parameter, for example: the first digital-to-analog converter 222 first A digital reference value 226 is converted into an analog signal and converted to an analog signal to the first current reference unit 232. The first current reference unit 232 is configured to generate a reference current signal (first electrical parameter) corresponding to the analog signal, for the sake of explanation. The first current reference unit 232 is shown as a separate unit. However, the first current reference unit 232 can be combined into a first digital-to-analog converter 222. For example, the first digital-to-analog converter 222 can be used to convert the digital reference value 226. Into the first electrical parameter. Also, the photo sensor 251 can sense the brightness of the illuminating light source 214. The second storage device 2 52 is connected to the photo sensor 251 and configured to store a plurality of second digital reference values 253 respectively corresponding to the brightness of the different illumination sources 214, wherein each of the second digital reference values 253 corresponds to at least one illumination source The working drive current of 214, the second digital reference 253 can be derived from the desired operating conditions of the simulated illumination source 214. For example, if the brightness of the illuminating source 214 is proportional to the operating drive current flowing through the illuminating source 214, the value of the operating drive current corresponding to the brightness of the illuminating source 214 can be derived from the operating conditions of the emulated illuminating source 214, and then the operating drive current value An analog to digital converter can be converted to a digital reference 253 and And stored in the second storage device 252. The second digital-to-analog converter 254 is connected to the second storage device 252 and the second digital reference value 253 for converting the brightness of the illumination source 214 into a second electrical parameter, and the second digital-to-analog converter 222 first uses the second digital reference. The value 253 is converted to an analog signal and converted to an analog signal to a second current reference unit 256, which is used to generate a second electrical parameter corresponding to the analog signal. For purposes of illustration, the second voltage reference unit 256 is shown as Separate units, however, the second voltage reference unit 256 can be combined into a second digital to analog converter 254, for example, the second digital to analog converter 254 can be used to convert the second digital reference value 253 into a second electrical parameter. The comparator 237 is a current comparator 237. The first current reference unit 232 is electrically connected to the first digital-to-analog converter 222 and the second voltage reference unit 256 is electrically connected to the second digital-to-analog converter 254 for comparison. a first electrical parameter (eg, a reference current value) and a second electrical parameter (eg, a feedback current value), and a drive signal DRV (eg, a drive bias current) corresponding to a difference between the two input currents, and a current regulator 212 The comparator 235 is connected and the operating current of the at least one illuminating source 214 is adjusted according to the driving bias current. In the embodiment, the current regulator 212 includes a metal oxide semiconductor (MOS) transistor 240, and the MOS transistor 240 is used to adjust the illuminating source. The working current of the MOS transistor 240 is connected to the current comparator 237, and receives the driving signal DRV, and the source terminal of the MOS transistor 240 is grounded. The drain terminal of the MOS transistor 240 is further connected to the light source 214 via the diode D. D is also grounded via a bypass capacitor C, which is used to protect the illuminating source 21 4 from malfunction of the controller 260 and for unwanted high frequency power. Drainage through the bypass capacitor C is grounded.

[0057] In a specific application, when the current comparator 237 detects that the second electrical parameter is different from the first electrical parameter, the current comparator 237 generates a driving signal DRV corresponding to the difference, and the driving signal DRV adjusts the current adjustment. The driving current of the device 212, for example, the use condition 225 is the ambient brightness in front of the display device. If the ambient brightness in front of the display device is 200 nits, the predetermined drive current is 5 A, and the first electrical parameter (reference current value) is 5 A, but this The brightness sensor 251 senses that the brightness of the light source 214 is 100 nits, the working drive current corresponding to the brightness of 100 nits is only 3 A, and the second electrical parameter (feedback current value) is 3 A, then the first electrical parameter and the second electrical parameter The difference between the two produces a relatively strong drive signal DRV, causing the operating drive current of the illuminating source 214 to increase to produce a higher backlight. Similarly, if the brightness of the illuminating source 214 is too bright, the corresponding working drive current is too large. Then, the current comparator 237 generates a relatively weak drive signal DRV, which reduces the operating drive current of the illuminating light source 214.

[0058] Therefore, the use condition 225 can be set in the current controller 260, and the current controller 260 is based on the use condition 2 25 automatically selects the corresponding digital reference value 226, and does not measure the working drive current of the illuminating light source 214, but sets the photo sensor 251 to directly sense the brightness to avoid the total illuminating time or different at the same current. The difference in brightness caused by the operating temperature, the corresponding working drive current is obtained by sensing the brightness, so that the adjustment of the working drive current is more accurate.

Referring to FIG. 13, in this embodiment, the steps are performed in a specific order. However, if executed in an appropriate circuit, the above steps may be performed in any specific order, and may be performed in any order or sequentially. First, in step 413, the conversion use condition is a first digital reference value, wherein the first digital reference value corresponds to a predetermined driving current of the illuminating light source. Step 423, then converting the digital reference value to a first electrical parameter (voltage or current). Step 433, sensing brightness of the corresponding illuminating light source, and converting the brightness of the illuminating light source to a second digital reference value, and then converting the second digital reference value to a second electrical parameter (voltage or current), wherein the second digital reference value corresponds to illuminating The working drive current of the light source. Step 443: Compare the first electrical parameter with the second electrical parameter. Next, in step 453, it is determined whether there is a difference between the measured first electrical parameter and the second electrical parameter. If there is a difference, step 463 is performed, and a driving bias current is generated according to the comparison result to adjust the working driving current of the illuminating light source, and steps 433 to 463 are repeatedly performed until there is no difference between the first electrical parameter and the second electrical parameter. , then it ends.

Based on the above, the present application provides a method and apparatus for controlling the operating drive current of a light source in a liquid crystal display system according to different usage conditions. In addition, in addition to measuring the working driving current of the illuminating light source 214, the present application may not measure the working driving current of the illuminating light source 214, but set the photo sensor 251 to directly sense the brightness to obtain the corresponding working driving current. In order to avoid the brightness drop caused by the total lighting time or different working temperature at the same current, the corresponding working driving current is obtained by sensing the brightness, so that the adjustment working driving current is more accurate.

[0061] It should be noted that, in the foregoing embodiments, the descriptions of the various embodiments are different, and the parts that are not described in detail in an embodiment may refer to related descriptions of other embodiments.

The above is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of various kinds within the technical scope disclosed by the present application. Equivalent modifications or substitutions are intended to be included within the scope of the present application. Therefore, the scope of protection of this application shall be subject to the scope of protection of the claims.

Claims

Claim

[Claim 1] A display system, comprising:

a display device having at least one illuminating light source;

a current controller, connected to the at least one illuminating light source, the current controller comprising: an operating temperature sensor, sensing an operating temperature of the at least one illuminating light source;

a storage device, coupled to the operating temperature sensor, configured to store a plurality of digital reference values respectively corresponding to different operating temperatures, wherein each digital reference value corresponds to a predetermined driving current of the at least one illuminating light source;

a digital-to-analog converter connected to the storage device and a digital reference value for converting an operating temperature of the at least one illuminating light source into a first electrical parameter;

a comparator connected to the digital-to-analog converter and configured to compare the first electrical parameter with a second electrical parameter corresponding to a working drive current of the at least one illuminating light source, and generate a driving bias current;

a current regulator, connected to the comparator and adjusting a working drive current of the at least one illuminating light source according to the driving bias current, wherein the driving bias current corresponds to the first electrical parameter and the second electrical parameter The difference between.

[Claim 2] The display system according to claim 1, wherein the comparator is a voltage comparator.

[Claim 3] The display system according to claim 2, wherein the first electrical parameter is a voltage corresponding to a predetermined driving current of the at least one illuminating light source.

[Claim 4] The display system according to claim 3, wherein the second electrical parameter is a feedback voltage corresponding to a working drive current of the at least one illuminating light source.

[Claim 5] The display system according to claim 1, wherein the comparator is a current comparator.

[Claim 6] The display system according to claim 5, wherein the first electrical parameter is a current value of the predetermined driving current corresponding to the at least one illuminating light source.

[Claim 7] The display system according to claim 6, wherein the second electrical parameter is a feedback power corresponding to a working drive current of the at least one illuminating light source.

[Claim 8] The display system according to claim 1, wherein the current controller further comprises a detector, the detector being coupled to the at least one illuminating light source and configured to measure the second electrical parameter.

[Claim 9] The display system of claim 1, wherein the predetermined drive current of the at least one illuminating light source is inversely proportional to the operating temperature.

[Claim 10] The display system according to claim 1, wherein the driving bias current corresponds to a difference between the first electrical parameter and the second electrical parameter.

[Claim 11] A current driving method of a display system, comprising:

Sensing an operating temperature sensor corresponding to an operating temperature of the at least one illuminating light source, and converting the operating temperature to a digital reference value, wherein the digital reference value corresponds to a predetermined driving current of the at least one illuminating light source;

Converting the digital reference value into a first electrical parameter;

Measuring a second electrical parameter corresponding to the working drive current of the at least one illuminating light source; comparing the first electrical parameter with the second electrical parameter, and generating a driving bias current according to the comparison result; and according to the driving offset The current adjusts a working drive current of the at least one illuminating light source.

[Claim 12] The method according to claim 11, wherein the predetermined driving current of the at least one illuminating light source is inversely proportional to the operating temperature.

[Clave 13] The method of claim 11, wherein the first electrical parameter and the second electrical parameter are compared by a voltage comparator.

[Claim 14] The method according to claim 13, wherein the first electrical parameter is a voltage corresponding to a predetermined driving current of the at least one illuminating light source.

[Claim 15] The method according to claim 14, wherein the second electrical parameter is a feedback voltage corresponding to a working drive current of the at least one illuminating light source.

[Clave 16] The method of claim 11, wherein the first electrical parameter and the second electrical parameter are compared by a current comparator.

[Claim 17] The method according to claim 16, wherein the first electrical parameter is a current value of the predetermined driving current corresponding to the at least one illuminating light source.

[Claim 18] The method according to claim 17, wherein the second electrical parameter is a feedback current corresponding to a working drive current of the at least one illuminating light source.

[Claim 19] The method of claim 11, wherein the driving bias current corresponds to a difference between the first and second electrical parameters.

[Claim 20] A current driving method for a display system, comprising:

Converting the digital reference value into a first electrical parameter;

Measuring a second electrical parameter corresponding to the working drive current of the at least one illuminating light source; comparing the first electrical parameter with the second electrical parameter, and generating a driving bias current according to the comparison result; Setting a current to adjust a working drive current of the at least one illuminating light source;

The predetermined driving current of the at least one illuminating light source is inversely proportional to the operating temperature; wherein the driving bias current corresponds to a difference between the first and second electrical parameters.