An economical wide-voltage adaptive driving method for segmented LCDs

Abstract

This invention discloses an economical wide-voltage adaptive driving method for segmented LCDs, comprising the following steps: selecting a driver chip with LCD driving capabilities, wherein the chip integrates a high-precision reference source, pin VREF1p2; retrieving the ADC conversion value of the driver chip at address 0x1FFFFB08 with a pre-stored 3V value for VREF1p2; obtaining the AD conversion value of the VREF1p2 pin at the current voltage through AD conversion; obtaining the current supply voltage VDD through a calculation formula; querying the value that the current LCDBIAS register should be configured with based on the current supply voltage VDD and driving voltage VLCD; updating LCDBIAS; and repeating steps S2-S5. This invention allows for dynamic adjustment of the LCD screen's driving voltage via software to adjust the display effect without the need for additional components; when voltage fluctuations exceed 0.2V, the driving voltage of the LCD screen can be automatically adjusted according to the supply voltage, thereby ensuring a stable display effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of voltage self-adaption, in particular to an economical segment LCD wide voltage self-adaption driving method. BACKGROUND

[0002] Segment LCD is mainly used to display numbers and fixed pen segments, and such LCD is cheap and low in power consumption, and is mainly used in portable products and small household appliances.

[0003] When segment LCD is used to display by multi-path common end scanning driving, due to the common relationship of row driving electrodes, the full-screen content will inevitably exist in three states of full display state, half display state and non-display state; the content of the display state should be displayed when working normally, and the content of the rest state should not be displayed; when the liquid crystal driving voltage is too high, the content of the half display state will be displayed, which is commonly known as ghosting; when the liquid crystal driving voltage is too low, the viewing angle of the full display state content will be biased, and the content to be displayed will be dim. At present, portable products are generally powered by rechargeable batteries, and the output voltage of the battery will decrease with the loss of stored power, and the tolerance of the driving voltage VLCD is generally ±0.2V, when the voltage exceeds this range, ghosting or dim display phenomenon will occur. Therefore, an economical segment LCD wide voltage self-adaption driving method is proposed to solve the above problems. SUMMARY

[0004] This section is intended to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, the abstract and the title, and such simplifications or omissions cannot be used to limit the scope of the present application.

[0005] In view of the above problems existing in the prior art economical segment LCD wide voltage self-adaption driving method, the present application is proposed.

[0006] Therefore, the purpose of the present application is to provide an economical segment LCD wide voltage self-adaption driving method, which can adjust the driving voltage of the liquid crystal screen by software dynamic adjustment to adjust the display effect without additional devices.

[0007] To solve the above technical problems, the present application provides the following technical scheme: an economical segment LCD wide voltage self-adaption driving method, comprising the following steps:

[0008] S1, selecting a driving chip with liquid crystal driving, and the chip integrates a high-precision reference source, the pin is VREF1p2, taking the conversion value of VREF1p2 at the position of 0x1FFFFB08 of the driving chip when 3V is pre-stored;

[0009] S2, obtaining the AD conversion value of the VREF1p2 pin under the current voltage through AD conversion;

[0010] S3, obtaining the current supply voltage VDD through a calculation formula;

[0011] S4, querying the value that the current LCDBIAS register should be configured according to the current supply voltage VDD and the driving voltage VLCD;

[0012] S5, updating the LCDBIAS;

[0013] S6, repeating steps S2-S5.

[0014] As a preferred scheme of the economic segment type LCD wide voltage adaptive driving method, wherein: the driving chip can control the driving voltage of the LCD by configuring the LCDBIAS register.

[0015] As a preferred scheme of the economic segment type LCD wide voltage adaptive driving method, wherein: the driving chip can work stably in the range of 1.6V≤VDDA≤5.5V, wherein VDDA represents the supply voltage.

[0016] As a preferred scheme of the economic segment type LCD wide voltage adaptive driving method, wherein: the reference voltage in the high-precision reference source in the driving chip can be sampled by the ADC after being output by the Buffer.

[0017] As a preferred scheme of the economic segment type LCD wide voltage adaptive driving method, wherein: the calculation formula in step S3 is:

[0018] VDD=(3*AD_data) / AD_3_Data

[0019] Wherein, AD_data is the AD conversion value of the VREF1p2 pin by the ADC, and AD_3_Data is the conversion value of VREF1p2 by the ADC when the driving chip pre-stores 3V at the position of address 0x1FFFFB08.

[0020] As a preferred scheme of the economic segment type LCD wide voltage adaptive driving method, wherein: after the supply voltage is calculated in step S3, the LCDBIAS register can be configured according to the configuration relationship diagram of the supply voltage and the liquid crystal screen driving voltage, and the driving voltage of the LCD is controlled.

[0021] The application has the advantages that the display effect can be adjusted by dynamically adjusting the driving voltage of the liquid crystal screen through software without adding extra devices, and when the voltage fluctuation exceeds 0.2V, the driving voltage of the liquid crystal screen can be automatically adjusted according to the power supply voltage, so that stable display effect is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0023] Figure 1 The program flow diagram of the economic segment type LCD wide voltage adaptive driving method of the present application;

[0024] Figure 2 The power supply voltage and liquid crystal screen driving voltage configuration relationship diagram of the economic segment type LCD wide voltage adaptive driving method of the present application. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification.

[0026] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited by the specific embodiments disclosed below.

[0027] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an independent or alternative embodiment that excludes other embodiments.

[0028] Thirdly, the present application is described in detail in conjunction with the schematic diagram, and in the detailed description of the embodiments of the present application, the cross-sectional view of the device structure is partially enlarged without general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the present application herein. In addition, three-dimensional spatial dimensions including length, width and depth should be included in actual manufacture.

[0029] REFERENCE Figures 1-2 An economic segment type LCD wide voltage adaptive driving method is provided, comprising the following steps:

[0030] S1, select a driving chip with liquid crystal driving, and the chip integrates a high-precision reference source, the pin is VREF1p2, take the conversion value of VREF1p2 of the driving chip at the position of address 0x1FFFFB08 and prestore 3V when ADC;

[0031] S2, obtain the AD conversion value of VREF1p2 pin under the current voltage through AD conversion;

[0032] S3, obtain the current power supply voltage VDD through the calculation formula;

[0033] S4, according to the current power supply voltage VDD and the driving voltage VLCD, query the value that the current LCDBIAS register should be configured;

[0034] S5, update LCDBIAS;

[0035] S6, repeat steps S2-S5.

[0036] The driving chip can control the driving voltage of the LCD by configuring the LCDBIAS register, specifically, the driving chip can work stably in the range of 1.6V≤VDDA≤5.5V, wherein VDDA represents the power supply voltage, and the reference voltage in the high-precision reference source in the driving chip can be sampled after being output by the Buffer, which is described in detail in Figure 2 .

[0037] The calculation formula in step S3 is:

[0038] VDD=(3*AD_data) / AD_3_Data

[0039] Wherein, AD_data is the AD conversion value of ADC to VREF1p2 pin, AD_3_Data is the conversion value of ADC to VREF1p2 when the driving chip pre-stores 3V at the position of address 0x1FFFFB08, after the power supply voltage is calculated in step S3, the LCDBIAS register can be configured according to the power supply voltage and the LCD driving voltage configuration relationship diagram, and the driving voltage of the LCD is controlled.

[0040] The application can dynamically adjust the driving voltage of the LCD to adjust the display effect without additional devices; when the voltage fluctuation exceeds 0.2V, the driving voltage of the LCD can be automatically adjusted according to the power supply voltage, so as to ensure stable display effect.

[0041] It should be noted that the above examples are only used to illustrate the technical solutions of the present application but not limit the present application. Although the present application is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced, without departing from the spirit and scope of the technical solutions of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. An economical segmental LCD wide voltage adaptive driving method, characterized in that, The method comprises the following steps: S1, selecting a driving chip with liquid crystal driving, and the chip is integrated with a high-precision reference source, and the pin is VREF1p2, the conversion value of VREF1p2 is obtained by the driving chip at the position of address 0x1FFFFB08 and when 3V is pre-stored in the ADC; S2, obtaining the AD conversion value of the VREF1p2 pin under the current voltage through AD conversion; S3, obtaining the current power supply voltage VDD through a calculation formula; wherein the calculation formula is: VDD=(3*AD_data) / AD_3_Data Wherein, AD_data is the AD conversion value of the VREF1p2 pin currently converted by the ADC, AD_3_Data is the conversion value of VREF1p2 converted by the ADC when 3V is pre-stored in the driving chip at the position of address 0x1FFFFB08, after the power supply voltage is calculated in step S3, the LCDBIAS register can be configured according to the configuration relationship diagram of the power supply voltage and the liquid crystal screen driving voltage, and the driving voltage of the LCD is controlled; S4, querying the value that the current LCDBIAS register should be configured according to the current power supply voltage VDD and the driving voltage VLCD; S5, updating the LCDBIAS; S6, repeating steps S2-S5.

2. The economical segmented LCD wide voltage adaptive driving method according to claim 1, characterized in that: The driving chip can control the driving voltage of the LCD by configuring the LCDBIAS register.

3. The economical segmented LCD wide voltage adaptive driving method according to claim 2, characterized in that: The driving chip can work stably in the range of 1.6V≤VDDA≤5.5V, wherein VDDA represents the power supply voltage.

4. The economical segmented LCD wide voltage adaptive driving method according to claim 3, characterized in that: The reference voltage in the high-precision reference source in the driving chip can be sampled by the ADC after being output by the Buffer.

5. The economical segmented LCD wide voltage adaptive driving method according to claim 1, wherein: The calculation formula in step S3 is: VDD=(3*AD_data) / AD_3_Data Wherein, AD_data is the AD conversion value of the VREF1p2 pin currently converted by the ADC, AD_3_Data is the conversion value of VREF1p2 converted by the ADC when 3V is pre-stored in the driving chip at the position of address 0x1FFFFB08.

6. The economical segmented LCD wide voltage adaptive driving method according to claim 5, wherein: After the power supply voltage is calculated in step S3, the LCDBIAS register can be configured according to the configuration relationship diagram of the power supply voltage and the liquid crystal screen driving voltage, and the driving voltage of the LCD is controlled.

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