CN104754798B - The brightness control method and device of key-press backlight - Google Patents

Abstract

The brightness control method and device of a kind of key-press backlight, the brightness control method of the key-press backlight include：Button panel sign is read from default memory, the bin value of the LED on the keypad is obtained；Using pulse width modulation wave corresponding with the bin value, the drive circuit of the LED on the keypad is controlled, the LED is lighted, the dutycycle of the bin value and the pulse width modulation wave has one-to-one relationship.Using methods described and device, can efficiently solve button on different key plate backlight illumination it is inconsistent the problem of.

Description

Brightness control method and device for button backlight

technical field

The invention relates to the field of intelligent control, in particular to a method and device for controlling the brightness of key backlights.

Background technique

Existing electronic equipment, such as vehicle consoles or mobile phones, etc., all have key backlights arranged in the keyboard housing. In a low-light environment, the backlight of the button is turned on to facilitate user operation. Generally, a light emitting diode (Light Emitting Diode, LED) is used as a key backlight.

Due to the production process, the same batch of LEDs may have multiple different BIN values, and different BIN values correspond to different brightness. Try to use LED lights with the same BIN value on the same key board, but the BIN values of the LEDs used on different key boards may be different, resulting in different brightness of the backlight of the keys on different key boards, which cannot meet customer requirements for brightness. The need for consistency.

Contents of the invention

The embodiment of the present invention solves the problem that the brightness of backlights of keys on different key boards is inconsistent.

In order to solve the above problems, an embodiment of the present invention provides a method for controlling the brightness of the key backlight, including: reading the key board identification from a preset memory, and obtaining the BIN value of the light-emitting diode LED on the key board; The pulse width modulation wave corresponding to the BIN value controls the driving circuit of the LED on the key board to light up the LED, and the BIN value has a one-to-one correspondence with the duty cycle of the pulse width modulation wave.

Optionally, the BIN value includes: the driving voltage of the LED, the color temperature of the LED, and the brightness of the LED.

Optionally, the blinking frequency of the LED is not lower than 60 Hz.

Optionally, the preset memory is an electrically erasable programmable read-only memory.

Optionally, the keypad identification is the keypad serial number.

In order to solve the above problems, an embodiment of the present invention also provides a brightness control device for key backlights, including: an acquisition unit, configured to read the keypad identification from a preset memory, and acquire the BIN value of the LED on the keypad The control unit is used to adopt the pulse width modulation wave corresponding to the BIN value, control the driving circuit of the LED on the key board, light the LED, and the ratio between the BIN value and the pulse width modulation wave The void ratios have a one-to-one correspondence.

Optionally, the BIN value includes: the driving voltage of the LED, the color temperature of the LED, and the brightness of the LED.

Optionally, the blinking frequency of the LED is not lower than 60 Hz.

Optionally, the preset memory is an electrically erasable programmable read-only memory.

Optionally, the keypad identification is the keypad serial number.

Compared with the prior art, the technical solutions of the embodiments of the present invention have the following advantages:

Since the brightness of the LED is related to the time ratio of the LED on and off, according to the preset corresponding relationship between the BIN value and the duty cycle of the pulse width modulation wave, the BIN value of the LED on the different key boards , by using pulse width modulation waves with different duty ratios to control the ratio of the on-off time of the LEDs, the backlight brightness of the keys on different key boards can be made the same.

Description of drawings

Fig. 1 is a flow chart of a brightness control method of a button backlight in an embodiment of the present invention;

Fig. 2 is a flow chart of another method for controlling the brightness of key backlights in an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a brightness control device for key backlights in an embodiment of the present invention.

detailed description

Due to the production process, the same batch of LEDs may have multiple different BIN values, and different BIN values correspond to different brightness. Try to use LED lights with the same BIN value on the same key board, but the BIN values of the LEDs used on different key boards may be different, resulting in different brightness of the backlight of the keys on different key boards, which cannot meet customer requirements for brightness. The need for consistency.

In the embodiment of the present invention, since the brightness of the LED is related to the ratio of the LED on and off time, according to the preset corresponding relationship between the BIN value and the duty ratio of the pulse width modulation wave, for different keypads The BIN value of the LED on the board, using pulse width modulation waves with different duty ratios to control the LED on and off time ratio, can make the backlight brightness of the keys on different key boards the same.

In order to make the above objects, features and advantages of the embodiments of the present invention more comprehensible, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

An embodiment of the present invention provides a method for controlling the brightness of a key backlight. With reference to FIG. 1 , specific steps will be described in detail below.

Step S101, read the identification of the key board from the preset memory, and obtain the BIN value of the LED on the key board.

In a specific implementation, the BIN value of the LED may include parameters such as the driving voltage of the LED, the color temperature of the LED, the brightness of the LED, and other parameters of the LED.

In a specific implementation, the identification information of the keypad may be obtained in advance and stored in a preset memory, and the preset memory may be an Electrically Erasable Programmable Read-Only Memory (EEPROM), or It can be other types of memory, as long as it can store the identification information of the keypad.

In a specific implementation, the keypad identifier may be a serial number of the keypad, and the serial number of the keypad may include BIN value information of the key backlight LEDs on the keypad.

Step S102, using the PWM wave corresponding to the BIN value to control the driving circuit of the LED on the keypad to light the LED, and the BIN value has a one-to-one correspondence with the duty cycle of the PWM wave.

In a specific implementation, corresponding to different BIN values, there may be a PWM wave corresponding to the duty cycle, and the driving circuit of the LED on the keypad is controlled by using the PWM wave corresponding to the duty cycle, that is, using the PWM wave corresponding to the duty cycle to control The time ratio between the on and off of the LED on the keypad. There is a one-to-one correspondence between the BIN value of the LED and the duty cycle of the PWM wave, which can be obtained through experimental data in specific implementation.

In a specific implementation, since the brightness of the LED can be related to the ratio of the LED on and off time, PWM waves with different duty ratios can be used to control the driving circuit of the LED, so that the LED is in a constant cycle of on and off. When the lighting time of the LED becomes longer and the extinguishing time becomes shorter in one cycle, the brightness of the LED increases; when the lighting time of the LED becomes shorter and the extinguishing time becomes longer in a cycle, the brightness of the LED becomes darker. By using PWM waves with different duty ratios to control the driving circuit of the LED, the brightness of the backlights on different key boards can be consistent.

In a specific implementation, the range of the blinking frequency of the LED may not be lower than 60 Hz, for example, the blinking frequency of the LED is 80 Hz. It can be understood that the blinking frequency of the LED can also be other values, as long as the blinking frequency of the LED is not lower than 60 Hz.

With the solution of the embodiment of the present invention, since the brightness of the LED is related to the ratio of the LED on and off time, according to the preset corresponding relationship between the BIN value and the duty cycle of the pulse width modulation wave, for different The BIN value of the LED on the keypad, using pulse width modulation waves with different duty ratios to control the LED on and off time ratio, can make the backlight brightness of the keys on different keypads the same.

In a specific implementation, the above solution can be further extended, which will be described in detail below through specific examples.

The embodiment of the present invention provides another method for controlling the brightness of the button backlight. Referring to FIG. 2 , the detailed steps will be described in detail below.

Step S201, storing the identification information of the keypad in a preset memory.

In the embodiment of the present invention, the identification information of the keypad can be obtained during the production process of the keypad, and the identification information of the keypad may be the serial number of the keypad, and the serial number of the keypad includes the key backlight information on the keypad The BIN value of the LED stores the serial number of the keypad in the preset memory, which can be EEPROM or other types of memory, as long as it can store the keypad identification information. The memory can be placed on the key board or other locations, and the location of the memory can be selected according to actual needs.

Step S202, read the key board identification from the preset memory, and obtain the BIN value of the LED on the key board.

In the embodiment of the present invention, when the device is turned on, the controller of the device can read the identification information of the keypad from the preset memory, and obtain the BIN value of the LED on the keypad according to the identification information of the key.

Step S203 , selecting the PWM wave corresponding to the BIN value to control the driving circuit of the LED on the key board.

In the embodiment of the present invention, according to the BIN value of the LED on the button board obtained in step S202, the corresponding relationship between the preset BIN value and the duty cycle of the PWM wave is used to control the button board by using the PWM wave corresponding to the duty cycle. on the LED drive circuit.

For example, there may be 4 key boards, the BIN values of the LEDs on each key board are the same, the BIN values of the LEDs between the key boards are different, corresponding to different BIN values, the brightness of the LEDs are different, and the LEDs on the 4 key boards have different BIN values. The BIN values corresponding to the LEDs are a, b, c, and d, respectively, where a<b<c<d, the brightness of the corresponding LEDs increases sequentially. Corresponding to different BIN values, PWM waves with different duty ratios are used to control the LED drive circuit. Corresponding to the LED whose BIN value is a on the key board, the PWM wave with a duty cycle of 95% can be used to control its driving circuit; corresponding to the LED with a BIN value on the key board, a duty cycle of 90% can be used PWM wave to control its drive circuit; corresponding to the LED with BIN value c on the key board, the PWM wave with a duty cycle of 85% can be used to control its drive circuit; corresponding to the LED with the BIN value on the key board The LED can control its drive circuit with a PWM wave with a duty cycle of 80%.

It can be understood that the above solution is just an example of using PWM waves with different duty ratios to control different BIN values. The PWM wave controls the LED drive circuit.

Step S204, turning on the button backlight LED on the button board.

Referring to FIG. 3 , an embodiment of the present invention also provides a brightness control device 30 for key backlights, including: an acquisition unit 301 and a control unit 302, wherein:

An acquisition unit 301, configured to read the keypad identification from a preset memory, and acquire the BIN value of the LED on the keypad;

The control unit 302 is configured to use the pulse width modulation wave corresponding to the BIN value to control the LED driving circuit on the key board to light up the LED, and the BIN value has a relationship with the duty ratio of the pulse width modulation wave One-to-one correspondence.

In a specific implementation, the BIN value may include: the driving voltage of the LED, the color temperature of the LED, and the brightness of the LED.

In a specific implementation, the blinking frequency range of the LED may not be lower than 60 Hz.

In a specific implementation, the preset memory may be an electrically erasable programmable read-only memory.

In a specific implementation, the keypad identification may be the keypad serial number.

Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can include: ROM, RAM, disk or CD, etc.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (8)

1. a kind of brightness control method of key-press backlight, it is characterised in that including：

Button panel sign is read from default memory, the bin value of the LED on the keypad is obtained；

Using pulse width modulation wave corresponding with the bin value, the drive circuit of the LED on the keypad is controlled, is utilized Between the lighting and extinguish of LED on the pulse width modulation wave control button plate of dutycycle corresponding with the bin value when Between compare, the dutycycle of the bin value and the pulse width modulation wave has one-to-one relationship；

The flicker frequency of the LED is not less than 60 hertz.

2. the brightness control method of key-press backlight as claimed in claim 1, it is characterised in that the bin value includes：It is described The brightness of LED driving voltage, the colour temperature of the LED and the LED.

3. the brightness control method of key-press backlight as claimed in claim 1, it is characterised in that the default memory is electricity EPROM.

4. the brightness control method of key-press backlight as claimed in claim 1, it is characterised in that the keypad is designated described Keypad sequence number.

5. a kind of brightness controlling device of key-press backlight, it is characterised in that including：

Acquiring unit, for reading button panel sign from default memory, obtains the bin value of the LED on the keypad；

Control unit, for using the LED's on pulse width modulation wave corresponding with the bin value, the control keypad Drive circuit, using the LED on the pulse width modulation wave control button plate of dutycycle corresponding with the bin value light and Time ratio between extinguishing, the dutycycle of the bin value and the pulse width modulation wave has one-to-one relationship；

The flicker frequency of the LED is not less than 60 hertz.

6. the brightness controlling device of key-press backlight as claimed in claim 5, it is characterised in that the bin value includes：It is described The brightness of LED driving voltage, the colour temperature of the LED and the LED.

7. the brightness controlling device of key-press backlight as claimed in claim 5, it is characterised in that the default memory is electricity EPROM.

8. the brightness controlling device of key-press backlight as claimed in claim 5, it is characterised in that the keypad is designated described Keypad sequence number.