CN211696891U

CN211696891U - Device for testing and verifying backlight of keyboard

Info

Publication number: CN211696891U
Application number: CN201922487606.3U
Authority: CN
Inventors: 李健韵; 曹智博; 汪金达; 曾令南
Original assignee: Intelligent Automation Equipment Zhuhai Co Ltd
Current assignee: Intelligent Automation Equipment Zhuhai Co Ltd; Intelligent Automation Zhuhai Co Ltd
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-10-16
Anticipated expiration: 2029-12-31

Abstract

The utility model provides a simple structure, simple operation and with low costs to the equipment of keyboard test and verification in a poor light. The utility model discloses a test system and KBD analog board, test system includes LED drive circuit, digital multimeter, interface, the KBD analog board is provided with a plurality of resistance and a plurality of LED according to actual keyboard backlight circuit, test system and KBD analog board pass through the interface electricity is connected, LED drive circuit to the KBD analog board power supply, a plurality of on the KBD analog board LED receives electroluminescence, a plurality of on the KBD analog board resistance plays step-down, current-limiting, sample effect separately, digital multimeter corresponds the hookup corresponding point and carries out electric current, voltage measurement. The utility model discloses be applied to the test field.

Description

Device for testing and verifying backlight of keyboard

Technical Field

The utility model relates to a test field especially relates to the equipment to test and verify that is shaded from the sun the keyboard.

Background

Due to the development of the electronic game market, in order to meet the requirements of high-end players, 1, backlight is added to the keys of the keyboard, so that the keyboard is more cool, and the user can clearly see the key letters under the condition of dim light; 2. the obvious brightness difference may occur between keys of the backlight keyboard and the keys, even in a single key, and the product experience of the user is seriously influenced by the difference, and if the difference is serious, the user can deny the whole keyboard. 3. In order to ensure that the keyboard backlight functions properly, the keyboard backlight needs to be detected. In summary, the market demands the detection of the backlight function of the keyboard, however, the detection device is relatively backward.

In reality: 1. in order to save cost, a keyboard manufacturer does not test the backlight of the keyboard or simply observes manually after being electrified to judge whether the brightness meets the requirement, and in order to save cost, the keyboard manufacturer does not test the backlight of the keyboard or observe by naked eyes after being electrified, is not rigorous and has no quality guarantee; the visual stimulation of different people is different, so the visual observation can have a large subjective factor, and the method has no relevant detection data and is not convincing.

2. Testing the complete keyboard finished product, putting the whole keyboard finished product into a dark box, detecting the brightness by using an optical instrument, disassembling and repairing if an unqualified product exists, detecting the finished product, putting the whole keyboard finished product into the dark box, and detecting the brightness by using the optical instrument; the method occupies large space, has high requirements on detection equipment, and has expensive optical instruments and extremely high detection cost. In addition, once unqualified finished products exist, the whole keyboard needs to be disassembled, time is consumed, the workload is large, the operation is complex, the detection efficiency is low, and large-scale mass production is not facilitated.

It is conceivable that such detection would not meet practical requirements, and therefore, it is highly desirable to develop a dedicated device for keyboard backlight testing and verification.

Disclosure of Invention

The utility model aims to solve the technical problem that overcome prior art not enough, provide a simple structure, simple operation and with low costs to the keyboard test in a poor light and equipment of verification.

The utility model adopts the technical proposal that: the utility model discloses a test system and KBD analog board, test system includes LED drive circuit, digital multimeter, interface, the KBD analog board is provided with a plurality of resistance and a plurality of LED according to actual keyboard backlight circuit, test system and KBD analog board pass through the interface electricity is connected, LED drive circuit to the KBD analog board power supply, a plurality of on the KBD analog board LED receives electroluminescence, a plurality of on the KBD analog board resistance plays step-down, current-limiting, sample effect separately, digital multimeter corresponds the hookup corresponding point and carries out electric current, voltage measurement.

The performance parameters of the LED driving circuit are consistent with those of the backlight LED driving circuit in the actual keyboard to be tested; and the parameters of the plurality of LEDs and the plurality of resistors on the KBD analog board are consistent with the parameters of the LEDs and the resistors in the keyboard backlight circuit to be tested.

The beneficial effects of utility model are that: because the utility model discloses a test system and KBD analog board, test system includes LED drive circuit, digital multimeter, interface, the KBD analog board is provided with a plurality of resistances, a plurality of LED according to actual keyboard backlight circuit, test system and KBD analog board pass through the interface electricity is connected, LED drive circuit to the KBD analog board power supply, on the KBD analog board a plurality of LED receive electroluminescence, on the KBD analog board a plurality of resistances play step-down, current-limiting, sample effect separately, digital multimeter corresponds the hookup corresponding point and carries out electric current, voltage measurement, and the actual luminous parameter who is surveyed keyboard backlight circuit is calculated to the science. The performance parameters of the LED driving circuit are consistent with those of the backlight LED driving circuit in the actual keyboard to be tested; and the parameters of the LEDs and the resistors on the KBD analog board are consistent with the parameters of the LEDs and the resistors in the keyboard backlight circuit to be tested. Therefore, the utility model has the advantages as follows:

1. low cost and small volume. Compared with the keyboard finished product test, the scheme has the advantages of lower cost, smaller occupied space, easy integration and large-scale popularization; 2. the application range is wide, and the keyboard backlight testing device is suitable for testing most of keyboards; 3. subjective factors of people are eliminated, objective test data are used for indicating the backlight quality of the keyboard, and the whole process is very visual and credible.

Drawings

FIG. 1 is a graph showing the relationship between LED brightness and forward current;

FIG. 2 is a schematic diagram of a typical application circuit of a driver chip for controlling current using PWM;

FIG. 3 is a schematic diagram of a typical application circuit of a driver chip using SET resistor to control current;

FIG. 4 is a backlight test system block diagram;

FIG. 5 is a circuit diagram of a portion of a KBD analog board;

fig. 6 is a schematic diagram of the J1 interface of the KBD platelet.

Detailed Description

As shown in fig. 1 to 6, an apparatus for testing and verifying backlight of a keyboard comprises a testing system and a KBD analog board, wherein the testing system comprises an LED driving circuit, a digital multimeter and an interface, the KBD analog board is provided with a plurality of resistors and a plurality of LEDs according to an actual keyboard backlight circuit, the testing system and the KBD analog board are electrically connected through the interface, the LED driving circuit supplies power to the KBD analog board, the plurality of LEDs on the KBD analog board are powered on to emit light, the plurality of resistors on the KBD analog board respectively perform voltage reduction, current limitation and sampling functions, the digital multimeter is correspondingly connected with corresponding points to perform current and voltage measurement, and the light emitting parameters of the actual keyboard backlight circuit to be tested are scientifically calculated.

The performance parameters of the LED driving circuit are consistent with those of the backlight LED driving circuit in the actual keyboard to be tested; and the parameters of the LEDs and the resistors on the KBD analog board are consistent with the parameters of the LEDs and the resistors in the keyboard backlight circuit to be tested.

The invention will be further described with reference to the following figures and examples:

as shown in fig. 1, the brightness of the LED is proportional to the forward current, so we can detect the brightness of the LED by detecting the forward current of the LED. The current methods for controlling the brightness of the LED mainly comprise 2 methods: 1. as shown in fig. 2, the PWM control is adopted, and the light emitting brightness of the LED is adjusted by controlling the duty ratio of the forward working current of the LED by using the PWM control signal; 2. as shown in fig. 3, linear control using the SET resistor is the simplest method, and only the external SET resistor is used in the LED driving IC to control the forward current of the LED, thereby controlling the brightness. However, the brightness controlled by the method cannot be adjusted, and the flexibility is poor.

Therefore, the brightness of the LED is controlled by the current output by the LED driving IC, and therefore, the backlight for detecting the keyboard actually detects the driving current output by the LED driving IC on the keyboard.

The embodiment provides a KBD analog platelet simulating a keyboard backlight, which is characterized in that related signals of an LED driving IC of a keyboard are connected to the platelet for detection, voltage and current data are collected, and the driving capability of an LED driver is analyzed through the voltage and current data.

As shown in FIG. 2, the test system comprises an LED, a sampling resistor, an interface, a DMM and an LED Driver. The KBD platelet is connected to an LED Driver of the keyboard, the LED on the KBD platelet simulates the LED on the keyboard, then the voltage at two ends of the sampling resistor is read by the DMM, the current flowing through the LED is calculated, and whether the LED Driver can drive the backlight of the keyboard and meet the brightness requirement or not is judged by analyzing the forward voltage and the current, namely the backlight on the actual keyboard cannot be driven.

1. Interface

The input interface of the keyboard LED Driver uses a simple and universal interface; different LEDCATHODE output PIN feet are selected through the interface, the number of LEDs of the KBD small plate can be freely selected, and the application range of the KBD small plate can be enlarged.

2.LED

The LED with low power consumption is selected and used, and is more attached to and close to the backlight lamps on most of keyboards, so that the keyboard backlight can be simulated to the highest degree, and test data are more real and credible.

3. Sampling resistor

The sampling resistor with high precision and large power is selected, so that the sampling data is more accurate and persuasive.

4.DMM

The DMM reads the voltage across the sampling resistor and reads the forward voltage. After the DMM reads the voltage at the two ends of the sampling resistor, the current passing through the LED is calculated by dividing the voltage by the resistance value of the sampling resistor. And comparing the current and voltage data with the parameter requirements of the keyboard backlight to judge whether the LED Driver can drive the keyboard backlight and can meet the requirements of a brightness lamp.

As shown in fig. 6, J1 is an interface of the KBD platelet, and an optional B2B connector is used; D1-D20 are LEDs, and low-power-consumption LEDs 3003LM2C are selected; R1-R4 are resistors, and high-precision sampling resistors are selected. Through careful type selection, the KBD platelet has better universality, higher cost performance and easy integration.

Calculation of LED Forward Current

I_f=V_r/R

Wherein

I_fIs forward current of LED

V_rFor sampling the voltage across the resistor

R is the resistance of the sampling resistor

For example, when 10 LEDs are used for simulation, the forward current I of the LED in FIG. 5_f=V_R3/R3=V_R3/10, wherein V_R3Is the voltage across R3 read by the DMM.

By the formula, the forward current of the LED can be rapidly calculated. When the LED uses the PWM mode, the forward current of the LED can be detected in real time by a calculation formula by controlling the frequency of DMM reading by a program.

The test and verification of the keyboard backlight are realized by using a low-cost and small-volume system scheme, a high-cost-performance backlight test and verification scheme is provided for the keyboard test equipment, and the test platelet is easy to integrate, low in cost and small in volume, so that large-scale application and popularization can be realized.

1. Low cost and small volume. Compared with the keyboard finished product test, the scheme has the advantages of lower cost, smaller occupied space, easy integration and large-scale popularization.

2. The application range is wide, and the keyboard backlight testing device is suitable for testing most of keyboards;

3. subjective factors of people are eliminated, objective test data are used for indicating the backlight quality of the keyboard, and the whole process is very visual and credible.

Claims

1. An apparatus for testing and verifying backlight of a keyboard, comprising: the device for testing and verifying the backlight of the keyboard comprises a testing system and a KBD (KBD) analog board, wherein the testing system comprises an LED driving circuit, a digital multimeter and an interface, the KBD analog board is provided with a plurality of resistors and a plurality of LEDs according to an actual keyboard backlight circuit, the testing system and the KBD analog board are electrically connected through the interface, the LED driving circuit supplies power to the KBD analog board, the plurality of LEDs on the KBD analog board are powered on to emit light, the plurality of resistors on the KBD analog board respectively play roles in reducing voltage, limiting current and sampling, and the digital multimeter is correspondingly connected with corresponding points to measure current and voltage.

2. The apparatus for testing and verifying backlighting of a keyboard of claim 1, wherein: the performance parameters of the LED driving circuit are consistent with those of the backlight LED driving circuit in the actual keyboard to be tested; and the parameters of the plurality of LEDs and the plurality of resistors on the KBD analog board are consistent with the parameters of the LEDs and the resistors in the keyboard backlight circuit to be tested.