CN108152625B

CN108152625B - Efficient general Sensor function detection system and algorithm for self-capacitance capacitive screen

Info

Publication number: CN108152625B
Application number: CN201711397843.XA
Authority: CN
Inventors: 俞世杰; 孙元鸿
Original assignee: Dijing Optoelectronics Shenzhen Co ltd
Current assignee: Dijing Optoelectronics Shenzhen Co ltd
Priority date: 2017-12-21
Filing date: 2017-12-21
Publication date: 2021-02-09
Anticipated expiration: 2037-12-21
Also published as: CN108152625A

Abstract

The invention provides a high-efficiency universal self-capacitance capacitive screen Sensor function detection system, which comprises an RC peripheral circuit module, a main chip control module, a bridging FPC circuit module, a self-capacitance Sensor screen body to be tested, a UART communication chip module and test software; the test software adopts an automatic scanning test mode, so that the time for each operator to click the start of the software is reduced, and the test efficiency is improved; the bridge FPC circuit module is adopted, all self-capacitance design schemes in the industry can be basically compatible, and therefore cost is saved; in addition, through the promotion of efficiency of software testing, the customer delivery period has been shortened.

Description

Efficient general Sensor function detection system and algorithm for self-capacitance capacitive screen

Technical Field

The invention relates to the technical field of capacitive screen function testing, in particular to a high-efficiency universal self-capacitance capacitive screen Sensor function detection system and algorithm.

Background

At present, the ITO structure of the self-capacitance capacitive screen is mainly designed by adopting a triangular pattern, and the actual measurement method in the production process is generally as follows:

in the development process: generally, a test board provided by a main control chip manufacturer is used for analyzing the performance of the capacitive screen and debugging parameters, and firmware capable of outputting Raw data (original capacitance sensing value) of each Sensor (sensitive element) is required to be burned by a capacitive screen control chip;

in the production process: detecting the feeding function of an FPCA (flexible printed circuit board) and the feeding function of an ITO film of the capacitive screen; in the link, firmware of Raw data needs to be burned into a main control chip of the capacitive screen, meanwhile, each product needs to be correspondingly configured with firmware for testing, an expensive test board needs to be used, the testing efficiency is low, and the testing efficiency of the current domestic and foreign scheme is 400-450 pcs/H; the manpower and material resources are wasted, and the delivery period of the product is influenced.

Therefore, each product needs to wait for the manufacture of a sample during testing, and simultaneously needs a special configuration file, and due to the fact that the used testing boards are different, the labor and material cost is increased, and the production efficiency is greatly reduced.

Disclosure of Invention

The invention aims to provide an efficient and general Sensor function detection system and algorithm for a self-capacitance capacitive screen aiming at the defects of the prior art, so that the test efficiency can be improved, and the test cost can be reduced.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a high-efficiency universal self-capacitance capacitive screen Sensor function detection system, which comprises an RC peripheral circuit module 1, a main chip control module 2, a bridge FPC circuit module 3, a self-capacitance Sensor screen body to be tested 4, a UART communication chip module 5 and test software 6, wherein the main chip control module is connected with the bridge FPC circuit module;

the main chip control module 2 is respectively connected with the RC peripheral circuit module 1, the bridging FPC circuit module 3 and the UART communication chip module 5; the UART communication chip module 5 is connected with a computer through a mini data line, and the bridging FPC circuit module 3 is connected with the self-contained Sensor screen body 4 to be tested;

the UART communication chip module 5, the main chip control module 2 and the RC peripheral circuit module 1 are arranged on a PCB, and the test software 6 is installed in the computer.

Further, the RC peripheral circuit module 1 sets a short-circuit detection range of the to-be-tested self-contained Sensor screen body 4, and the main chip control module 2 collects the content value data of each channel of the to-be-tested self-contained Sensor screen body 4 and transmits the data to the test software 6 through the UART communication chip module 5 for testing.

Further, the self-contained Sensor screen body 4 to be tested is of a PAD structure, and the center distance between the two PADs is 0.5-0.8 mm.

The invention also provides an algorithm of the high-efficiency universal Sensor function detection system of the self-capacitance capacitive screen, which comprises the following steps:

s1, using the main chip control module as I²The slave C is used for storing and supplying I²C, reading data by the main equipment;

s2, pressing the self-locking switch, starting I after electrifying²C, a communication module and setting an initial value of a register; address [0] per channel]Defaults to 0x00 and then begins to enter the main loop;

s3, scanning all ITO channel Data in a main cycle, converting the Data through an AD conversion chip carried by a main chip control module, storing the Data in a register Address [0]. Address [ N ], and obtaining Raw Data Base values of a Sensor of each channel;

s4, after connecting products, repeating S2 and S3 to obtain a Sensor Raw Data value, and subtracting Raw Data Base Data of each channel from the Data to obtain Sensor Raw Data Differ Data of each channel;

s5, making configuration files, setting according to the actual channel number of the product, and respectively recording Raw Data Differ Data of each pair of ITO opposite channels on an X axis and a Y axis; by controlling the difference value between the Raw Data Differ Data and the relative ITO channel X-Y, upper and lower limits are set for controlling, and the on-off of the product can be detected by the method;

s6, measuring the short circuit range of the product by using an RC peripheral circuit module in a resistance measuring mode, wherein 5 mega ohms is set at present;

and S7, finally judging whether the function of the self-contained Sensor screen body to be tested is qualified or not by the open-circuit and short-circuit detection and the OK/NG display of the software.

The invention has the beneficial effects that: the test software adopts an automatic scanning test mode, so that the time for each operator to click the start of the software is reduced, and the test efficiency is improved; the bridge FPC circuit module is adopted, all self-capacitance design schemes in the industry can be basically compatible, and therefore cost is saved; in addition, through the promotion of efficiency of software testing, the customer delivery period has been shortened.

Drawings

Fig. 1 is a schematic connection diagram of a Sensor function detection system of an efficient general-purpose self-capacitance capacitive screen.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, a high-efficiency universal self-capacitance capacitive screen Sensor function detection system comprises an RC peripheral circuit module 1, a main chip control module 2, a bridge FPC circuit module 3, a self-capacitance Sensor screen body to be tested 4, a UART communication chip module 5 and test software 6;

The UART communication chip module 5 is a universal asynchronous receiver and transmitter, is a chip for controlling a computer and serial equipment, provides an RS-232C data terminal equipment interface, and the computer can communicate by using the serial equipment of the RS-232C interface and a modem,

the RC peripheral circuit module 1 sets a detection short-circuit range of the self-contained Sensor screen body 4 to be tested, and the main chip control module 2 collects the capacity value data of each channel of the self-contained Sensor screen body 4 to be tested and transmits the data to the test software 6 for testing through the UART communication chip module 5.

Wherein, the main chip control module 2 adopts STM32F103X8 micro control chip, including I²C communication module, can be regarded as I²C master device, through I²And the communication interface C is used for reading and writing data of each channel of the self-contained Sensor screen body 4 to be tested, and the main chip control module 2 comprises 2 12-bit DAC modules.

The to-be-tested self-contained Sensor screen body 4 is of a PAD structure, the center distance between two PADs is 0.5-0.8 mm, and the to-be-tested self-contained Sensor screen body can meet the requirement of testing the design function of the to-be-tested self-contained Sensor screen body in the current industry.

That is, the bridge FPC circuit module 3 can select the corresponding bridge FPC circuit module 3 according to the PAD pin of the product by adopting the design standard in the industry at present.

The RC peripheral circuit module 1 comprises a plurality of 500K resistors, a plurality of chip capacitors and other devices, is matched with the main chip control module 2, and is used for transmitting alternating current components of input signals, processing external signal interference and setting functional short-circuit range detection of the self-contained Sensor screen body 4 to be tested by changing the size of the resistors.

A hardware part of a high-efficiency universal self-capacitance capacitive screen Sensor function detection system comprises:

selecting a corresponding bridge FPC circuit module 3 according to the distance between PADs of the product, wherein one end of the bridge FPC circuit module is fixed on the jig frame, and the other end of the bridge FPC circuit module is connected with a circuit board of the main chip control module 2;

the main chip control module 2, the RC peripheral circuit module 1 and the UART communication chip module 5 are designed and integrated on a PCB, and the other end is connected with a computer through a Mini data line.

A software part of a high-efficiency universal self-capacitance capacitive screen Sensor function detection system comprises:

information transmission: after the USB is electrified, the bridge FPC circuit module 3 is connected with a product to be tested and the test board, and the main chip control module 2 provides standard I²The communication interface C is communicated with the main chip control module 2 through the SCL and the SDA, and the main controller controls the Reset and INT port states to set during power-on initialization so as to transmit data;

data transmission (take device 0xBA/0xBB as an example): initiated by the main chip control module 2, the effective starting signal is: while SCL remains "1", a jump from "1" to "0" occurs on SDA. Either the address information or the data stream is transmitted after the start signal. All connections are to²The slave devices on the C bus detect the 8-bit address information sent after the start signal on the bus and react correctly. When receiving the address information matched with the master chip control module 2, the master chip control module changes the SDA to the output port, and sets the output port to "0" as a response signal. If address information which is not matched with the address information is received, the address information is not 0XBA or 0 XBB.

After receiving the response signal, the main CPU transmits 16-bit address information of the first register address, setting the register address to be read. After receiving the response, the main chip control module 2 resends the initial signal once, and sends a read operation: 0 XBB. After receiving the response, the main chip control module 2 starts to read data;

after reading the data, sending I through the UART communication chip module 5²C, converting the USB serial port chip into a computer; testing through configuration software;

an algorithm of a high-efficiency universal Sensor function detection system of a self-capacitance capacitive screen comprises the following steps:

Testing efficiency: the test software adopts an automatic scanning test mode, so that the time for each operator to click the start of the software is reduced, and the test efficiency is improved;

and (3) testing cost: the bridge FPC module is adopted, all self-capacitance design schemes in the industry can be basically compatible, the manufacturing cost of the bridge FPC module is about 2 yuan/piece, the service life is calculated according to the proportion of 1:1000, the cost of a universal test frame is about 20 units, and each 500 yuan is calculated; if the order is 1kk per month, the monthly test fee is about 12000 yuan;

the traditional application test fixture demand is 1kk order per month, 10 fixtures are needed for standby in each model according to 20 models, and the test cost is about 10 ten thousand;

the cost for purchasing the jig is saved by about 8 ten thousand per month while the increase of labor cost is not considered.

The traditional test efficiency is low: in a traditional test scheme, such as an industry top-grade and Tuita self-contained design scheme, firstly, burning firmware of FPCA (flexible printed circuit board) incoming materials of corresponding models is required, then, special test software is used for carrying out function detection, as the software needs to detect some channel functions of the FPC and needs to be operated by personnel, the software starts to operate by clicking a start button with a mouse; the product testing time is prolonged; the software only tests the testing efficiency: averaging 6.5 seconds per piece (remark: critical value (TBD) exists in part of products, scribing is needed, the testing efficiency is about 20 s), and the time for taking the products by personnel is about 400-450 pieces per hour;

the technical scheme is as follows: the technical detection system adopts a scanning mode, software reads and processes data all the time, then tests through set configuration software, and displays results after judging the product OK/NG; the time is about 1.5S; the average test efficiency is about 1400-1500 pcs;

through the improvement of the testing efficiency, the customer delivery period is shortened.

The above-mentioned embodiments only express the embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a high-efficient general Sensor function detecting system from capacitive screen which characterized in that: the device comprises an RC peripheral circuit module (1), a main chip control module (2), a bridge FPC circuit module (3), a self-contained Sensor screen body to be tested (4), a UART communication chip module (5) and test software (6);

the main chip control module (2) is respectively connected with the RC peripheral circuit module (1), the bridging FPC circuit module (3) and the UART communication chip module (5); the UART communication chip module (5) is connected with a computer through a mini data line, and the bridging FPC circuit module (3) is connected with the self-contained Sensor screen body (4) to be tested;

the UART communication chip module (5), the main chip control module (2) and the RC peripheral circuit module (1) are arranged on a PCB, and the test software (6) is installed in the computer;

the RC peripheral circuit module (1) sets a detection short-circuit range of the self-contained Sensor screen body (4) to be tested, and the main chip control module (2) collects the capacity value data of each channel of the self-contained Sensor screen body (4) to be tested and transmits the capacity value data to the test software (6) for testing through the UART communication chip module (5);

the method comprises the following steps:

s1, the master chip control module is used as an I2C slave device for storing data read by the I2C master device;

s2, pressing the self-locking switch, starting the I2C communication module after being electrified, and setting an initial value of a register; the value of each channel Address [0] is set to 0x00 by default, and then the main loop is started to enter;

2. The system for detecting the Sensor function of the high-efficiency universal self-capacitance capacitive screen according to claim 1, is characterized in that: the self-contained Sensor screen body (4) to be tested is of a PAD structure, and the center distance between two PADs is 0.5-0.8 mm.