WO2012142928A1 - 用于测试电路板上触摸屏功能电路的方法及装置 - Google Patents

用于测试电路板上触摸屏功能电路的方法及装置 Download PDF

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Publication number
WO2012142928A1
WO2012142928A1 PCT/CN2012/074065 CN2012074065W WO2012142928A1 WO 2012142928 A1 WO2012142928 A1 WO 2012142928A1 CN 2012074065 W CN2012074065 W CN 2012074065W WO 2012142928 A1 WO2012142928 A1 WO 2012142928A1
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WIPO (PCT)
Prior art keywords
touch screen
circuit board
circuit
terminals
screen function
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Application number
PCT/CN2012/074065
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English (en)
French (fr)
Inventor
林文
王学成
何超
Original Assignee
青岛海信移动通信技术股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Priority claimed from CN201110111456.1A external-priority patent/CN102288894B/zh
Priority claimed from CN201110293825.3A external-priority patent/CN102445651B/zh
Application filed by 青岛海信移动通信技术股份有限公司 filed Critical 青岛海信移动通信技术股份有限公司
Publication of WO2012142928A1 publication Critical patent/WO2012142928A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/28—Testing of electronic circuits, e.g. by signal tracer
    • G01R31/2801—Testing of printed circuits, backplanes, motherboards, hybrid circuits or carriers for multichip packages [MCP]
    • G01R31/281—Specific types of tests or tests for a specific type of fault, e.g. thermal mapping, shorts testing
    • G01R31/2815—Functional tests, e.g. boundary scans, using the normal I/O contacts

Definitions

  • the present invention relates to the field of circuit board function detection technology, and in particular to a test method and a test apparatus for detecting a touch screen function circuit on a circuit board proposed for a circuit board supporting a resistive touch screen.
  • the production line usually produces some fixtures, that is, test fixtures, and the touch screen is mounted on the test fixture.
  • the operator first loads the FPC connector of the touch screen into the FPC connection of the mobile phone circuit board before performing the circuit board inspection.
  • the mobile phone circuit board then put the mobile phone circuit board into the test fixture to power the mobile phone circuit board and the touch screen, and operate the touch screen to detect the touch screen function circuit on the mobile phone circuit board.
  • the existing test methods of the mobile phone circuit board mainly have the following disadvantages: 1. Before each test of the touch screen function circuit of the mobile phone circuit board, the operator needs to connect the touch screen with the mobile phone circuit board, thereby increasing the operation worker's 2. In the test process, the operator is required to subjectively judge whether the touch screen function circuit of the circuit board is operating normally, that is, whether the correct response is made, so that the misjudgment problem cannot be avoided, and the foolproof measures are lacking;
  • the touch screen is used for the detection process of the mobile phone circuit board, and not only requires a large number of touch screens, but also the test of the production line body will lose many touch screens, which also causes an increase in the test cost. Summary of the invention
  • the object of the present invention is to provide a method for testing a touch screen function circuit on a circuit board, which can complete the test task of the touch screen function circuit on the circuit board without applying the actual touch screen to the production line. And the test results no longer depend on the subjective judgment of the operator.
  • a method for testing a touch screen function circuit on a circuit board, the circuit board supporting a 4-wire resistive touch screen, and the circuit board is provided with four terminals X+, X-, Y+, ⁇ - for connecting the resistive touch screen; Two resistors are connected in series between the ⁇ + and X- terminals, and two other resistors are connected in series between the ⁇ + and ⁇ - terminals, and the intermediate nodes of the two resistor series branches are connected together; The board sequentially applies a bias voltage to the two resistor series branches; respectively, reads the divided voltage values of the intermediate nodes of the two resistor series branches; determines whether the touch screen function circuit of the circuit board is normal according to the two divided voltage values read .
  • the circuit board first applies a bias voltage to the ⁇ + terminal through its touch screen function circuit, and biases the X-terminal to 0V, and reads the voltage value of the ⁇ + or ⁇ -terminal to obtain a partial pressure value; Then apply a bias voltage to the ⁇ + terminal, and bias the ⁇ -terminal to 0V, and read the voltage value of the ⁇ + or X- terminal to obtain another partial voltage value.
  • the specific process of determining whether the touch screen function circuit of the circuit board is normal according to the two divided voltage values read may use the following two design methods:
  • One is to perform analog-to-digital conversion on the received partial voltage value by using a touch screen function circuit, and generate coordinate values to be transmitted to the CPU on the circuit board; the CPU feeds back coordinate values to the computer; the computer will receive the coordinates The value is compared with the theoretical coordinate value. If they are the same, it is determined that the touch screen function circuit is normal, and the determination result is displayed.
  • the second is to use the touch screen function circuit to perform analog-to-digital conversion on the received partial pressure value, and generate coordinate values to be transmitted to the CPU on the circuit board; the CPU compares the coordinate value with the theoretical coordinate value, and if the same, determines The touch screen function circuit is normal, and the control signal is output to the actuator to control the actuator action. By observing the action of the actuator, it is possible to clearly determine whether the touch screen function circuit is normal.
  • the magnitudes of the bias voltages applied to the two resistor series branches are equal, and each The resistances of the two resistors in the resistor series branch are equal.
  • the computer After receiving the coordinate value, the computer determines whether the values of the X coordinate and the Y coordinate are equal. If they are equal, it determines that the touch screen function circuit is normal.
  • the two resistors connecting the X+ and Y+ terminals can also be zero-resistance or non-zero resistors; and the two resistors connecting the X- and Y- terminals must be non-zero resistors. To ensure the normal operation of the test.
  • the invention also provides a device for testing a touch screen function circuit on a circuit board, which is used for testing a circuit board supporting a 4-wire resistive touch screen, and is provided with a resistive touch screen on the circuit board.
  • a resistive touch screen on the circuit board.
  • the other two resistors are connected in series and connected between the ⁇ + and ⁇ - terminals, and the intermediate nodes of the two resistor series branches are connected and connected; the circuit board passes through ⁇ +, ⁇ -, ⁇ +, ⁇ - four terminals sequentially apply a bias voltage to the two resistor series branches, and respectively read the partial voltage values of the intermediate nodes of the two resistor series branches, according to the reading The two divided voltage values obtained determine whether the touch screen function circuit on the circuit board is normal.
  • the circuit board sequentially applies a bias voltage to the four terminals of the ⁇ +, ⁇ -, ⁇ +, ⁇ - and uses the touch screen controller thereon to receive the voltage division value, and after performing analog-to-digital conversion on the partial pressure value , generating coordinate values transmitted to the CPU on the board;
  • the CPU is connected to the computer or the actuator; when connected to the computer, the coordinate value is fed back to the computer, and the computer compares the received coordinate value with the theoretical coordinate value. If the same, the touch screen function circuit is determined to be normal, and the determination result is displayed.
  • the CPU compares the received coordinate value with the theoretical coordinate value. If they are the same, it determines that the touch screen function circuit is normal, outputs a control signal to the actuator, controls the actuator, and then observes the actuator. Action or not, to determine whether the touch screen function circuit is normal.
  • the two resistor series branches are respectively connected to the X+, Y+ terminals through a switching path of a switching circuit, or in series with one of the resistors. Both ends of the circuit are respectively connected to a switching path of a switching circuit, and pass the switch
  • the paths are respectively connected to the x+ and x- terminals or respectively connected to the ⁇ + and ⁇ - terminals; the two switch circuits are controlled to be turned on at the beginning of the test, and the two test circuits can be controlled by the test start command signal sent by the computer. Turn on, start the board test process.
  • test fixture for mounting the circuit board is further disposed in the device, and the test fixture is provided with ⁇ +, ⁇ -, ⁇ +, ⁇ for four terminals on the circuit board.
  • the analog circuit is correspondingly connected to the four probes.
  • the present invention uses four ordinary resistors instead of the actual resistive touch screen for detecting a circuit board supporting a 4-wire resistive touch screen, since the test process does not need The actual resistive touch screen is used, so the test cost is greatly reduced, and damage to the touch screen can be avoided. Further, with the test method and test apparatus of the present invention, the operator does not need to connect the circuit board to the touch screen before the test, thereby reducing the workload of the operator. Moreover, the test results are automatically generated, eliminating the possibility of subjective misjudgment by the operator.
  • FIG. 1 is a schematic structural view of a conventional 4-wire resistive touch screen
  • FIG. 2 is a circuit schematic diagram for detecting an X-axis coordinate of a touch point position of an existing 4-wire resistive touch panel
  • FIG. 3 is a circuit schematic diagram for detecting a ⁇ -axis coordinate of a touch point position of an existing 4-wire resistive touch panel
  • FIG. 4 is a system architecture diagram of an embodiment of an apparatus for testing a touch screen function circuit on a circuit board according to the present invention
  • Figure 5 is a circuit schematic diagram of an embodiment of the resistive touch screen analog circuit of Figure 4;
  • Figure 6 is a flow chart of one embodiment of the test program run by the computer of Figure 4;
  • Figure 7 is a resistive version of Figure 4.
  • the current resistive touch screen has a similar appearance to the display screen. By touching different positions of the screen, different resistance values are provided externally, so that the touched position on the screen corresponds to the resistance value, and the input device can be used as an input device. Intuitively control the entire machine to perform the corresponding processing operations.
  • the touch display attaches the touch screen to the surface of the display for use with the display. After the analog electrical signal generated by the touch is converted into a digital signal, the coordinates of the touched point are calculated by the processor, thereby obtaining the operator's intention and responding.
  • the 4-wire resistive touch screen is used more in practical applications.
  • the touch screen is composed of 4 transparent layers: the bottom layer is the base layer, usually made of glass or plexiglass; the top is a plastic layer, which is hardened. Smooth and scratch-resistant; between the upper and lower layers are two metallic conductive layers, as shown in Figure 1, which are insulated by tiny transparent isolation points. When the finger touches the screen, the two conductive layers are in contact at the touch point.
  • the two metal conductive layers of the touch screen are used to measure the coordinates of the X-axis and the Y-axis, respectively.
  • One layer (X layer) is provided with a vertical bus on the left and right edges of the screen, denoted as ⁇ +, X-, for X.
  • the measurement of the axis coordinates is shown in Figure 1.
  • the other layer (Y layer) is provided with a horizontal bus on the upper and lower edges of the screen, denoted as Y+, ⁇ -, for the measurement of the axis coordinates, which constitutes 4 Four leads of a linear resistive touch screen. When a voltage is applied to a pair of leads, a uniform voltage distribution is formed on the conductive layer.
  • the touch screen function circuit usually includes a touch screen controller or a function of integrating the touch screen controller in the CPU of the mobile phone.
  • the touch screen controller is responsible for voltage biasing the four leads of the touch screen, and collecting voltage values in the X-axis direction and the Y-axis direction, and converting the analog quantity into a digital quantity after performing ADC conversion, thereby obtaining a touch point on the touch screen.
  • the coordinate value The touch screen controller transmits the obtained coordinate value to the CPU of the mobile phone, and the CPU changes the screen of the display screen according to the change of the coordinate value, thereby realizing the response of the mobile phone to the operation of the touch screen.
  • the invention aims at the above characteristics of the current 4-wire resistive touch screen, and improves the functional test automatic test equipment for testing the circuit board circuit, so that the circuit board can be completed without the need of the circuit board connecting the actual touch screen. Performance detection of the touch screen function circuit.
  • the following takes the mobile phone motherboard as the circuit board to be tested as an example, and the method and device for testing the touch screen function circuit on the test circuit board are described in detail by two specific embodiments.
  • Embodiment 1 In the test apparatus of this embodiment, an analog circuit for simulating a 4-wire resistive touch screen, which is formed by connecting four resistors R1, R2, R3 and R4, is mainly provided, as shown in FIG.
  • the analog circuit is connected to the X+, X-, Y+, and ⁇ - terminals of the mobile phone main board for connecting the 4-wire resistive touch screen, and the touch screen function circuit on the mobile phone main board can be tested.
  • two resistors R1 and R2 may be connected in series to form a resistor series branch, which is connected between the X+ and X- terminals; and the other two resistors R3 and R4 are connected in series to form a second resistor in series.
  • the branch is connected between the ⁇ +, ⁇ -terminals; then the intermediate nodes C of the two resistor series branches are connected together.
  • a test computer is also provided in the test device, and a test fixture for mounting the circuit board 2 to be tested (ie, the mobile phone motherboard in this embodiment) is provided. 3 and a test circuit board 4 connected to the test fixture 3, as shown in FIG.
  • Four probes XI, ⁇ 0, ⁇ 1, and ⁇ are formed on the test fixture 3 for respectively connecting with the four terminals ⁇ +, ⁇ -, ⁇ +, ⁇ on the main board of the mobile phone.
  • the analog circuit is disposed on the test circuit board 4, and the resistor series connected by the resistors R1 and R2 are connected in series to the probes XI and X0.
  • the second resistor series branch formed by connecting resistors R3 and R4 in series is connected between the probes Y1 and ⁇ 0.
  • the mobile phone main board can be used to sequentially apply a bias voltage to the two resistor series branches. For example, a certain bias voltage can be first applied between the ⁇ + and X- terminals of the main board. , and no voltage is applied between the ⁇ + and ⁇ - terminals. At this time, the voltage value of C at the intermediate node of the series branch of the resistors R1 and R2 can be obtained by reading the voltage value on the ⁇ + terminal or the ⁇ -terminal. .
  • the voltage value is used to obtain the voltage division value of C at the intermediate node of the series branch of the resistors R3 and R4.
  • the coordinate values can be converted and recorded as actual coordinate values. Since the bias voltage applied to the two resistor series branches via the main board and the resistance values of the four resistors R1 - R4 are known in advance, the theoretical coordinate value of point C can be calculated in advance. The actual coordinate value is compared with the theoretical coordinate value.
  • the touch screen function circuit on the main board accurately obtains the coordinate information, and the touch screen function circuit is normal.
  • the actual coordinate value fed back through the touch screen function circuit is different from the theoretical coordinate value, it is considered that the touch screen function circuit cannot accurately acquire the coordinate information, and the touch screen function circuit is faulty. Therefore, in the test process of the mobile phone motherboard, the performance of the touch screen function circuit on the circuit board can be accurately detected without connecting the actual touch screen on the circuit board, thereby simplifying the test work and reducing the test cost.
  • the testing technique of the embodiment since the actual touch screen needs to be connected during the motherboard test, it is easy to cause a problem that the state of the motherboard circuit is misjudged due to the problem of the touch screen itself. After using the testing technique of the embodiment, the occurrence of such problems can be well avoided, and the accuracy of the test is improved.
  • a switch circuit is respectively connected to the two resistor series branches on the test circuit board 4, and the switch paths of the two switch circuits are respectively connected to each other.
  • the control terminal receives the test start command signal P1 output by the computer, and when testing the touch screen function circuit on the main board, outputs a valid test start command signal P1, and controls
  • the two-way switch circuit is turned on, thereby implementing the communication between the two resistor series branches in the two pairs of probes X1 /X0, Y1 /Y0.
  • the present embodiment uses two NPN-type transistors Q1, Q2 to design the switching circuit, as shown in FIG. Connect the collector of the transistor Q1 to the probe XI, the emitter connection resistor R1, and then connect the probe X0 through the resistor R2; connect the collector of the transistor Q2 to the probe Y1, the emitter connection resistor R3, and then pass the resistor R4 is connected to the probe Y0; the bases of the two transistors Q1, Q2 are connected to the computer through the communication control line ct l, and receive the test start command signal P1 issued by the data set card in the computer, and the test start command signal P1 is When the level is high, the saturation is turned on, and the series connection of the resistors between the two pairs of probes X1/X0 and Y1/Y0 is connected to start the detection of the touch screen function circuit.
  • the switching circuit can also use other thyristors, MOSFETs, and other components having switching functions for circuit design. This embodiment is not limited to the above examples.
  • test method of this embodiment will be specifically described below with reference to FIG.
  • the mobile phone motherboard 2 to be tested is mounted on the test fixture 3, as shown in FIG. 4, the test fixture 3 is closed, so that the four probes XI, ⁇ 0, ⁇ 1, ⁇ 0 on the fixture are just on the mobile phone motherboard 2
  • the four terminals ⁇ +, ⁇ -, ⁇ +, ⁇ 0 for connecting the resistive touch screen are connected.
  • a communication control line c 11 is connected between the test circuit board 4 and the computer 1. In this embodiment, it can be specifically connected to a data output port of the data collection card of the computer 1 to receive the test of the output of the computer 1.
  • the command signal P1 is started.
  • the communication data line da ta is connected between the mobile phone main board 2 and the computer 1 host to realize two-way communication of data between the two. As a result, the hardware connection work is completed.
  • the S60 operator inputs an instruction to start the test through the computer 1, and after receiving the start command, the computer 1 outputs a valid test start command signal P1 through its data collection card, and transmits it to the test circuit board 4 via the communication control line c11.
  • the test circuit board 4 transmits the received test start command signal P1 to the bases of the NPN transistors Q1 and Q2, and controls the transistors Q1 and Q2 to be saturated, and connects the resistors R1 and R2 in series between the probes XI and X0. , The resistors R3 and R4 are connected in series between the probes Y1 and ⁇ 0.
  • the computer 1 establishes a communication link with the mobile phone main board 1 through the communication data line da ta, and sends a request for feedback to the touch screen coordinate value to the mobile phone main board 2.
  • the touch screen controller U1 applies a certain bias voltage to the X+ terminal in real time.
  • the touch screen controller U1 considers that the touch screen is not touched at this time; and when the touch screen controller U1 detects that there is a voltage on the Y+ terminal thereof, it is considered that the touch screen is touched, and the touch screen controller U1 starts to sequentially turn to the X+, Y+ terminals.
  • a bias voltage is applied.
  • the touch screen controller U1 first applies a certain bias voltage to the X+ terminal, such as the reference voltage VREF, and biases the X-terminal to 0V, and reads the voltage value on the Y+ or Y- terminal. Obtain a voltage divider value V x ; Then, stop applying a bias voltage between the X+ and X- terminals, and then apply a bias voltage to the Y+ terminal, such as the reference voltage VREF, and bias the Y-terminal to 0V. , read the voltage value on the X+ or X- terminal to get another partial voltage value V Y . It can be seen from the circuit shown in Figure 5:
  • V x R2 ;
  • V Y xR4 ;
  • the touch screen controller U1 performs ADC conversion on the two divided voltage values V x and V Y that are read, and can calculate the coordinate value of the generated C point, that is, the coordinate value of the touch point on the touch screen is obtained.
  • the touch screen controller U1 transmits the generated coordinate value to the CPU on the mobile phone main board 1 through the I 2 C bus, and the CPU communicates with the computer 1 through the communication data line da ta to feed back the coordinate value to the computer 1 .
  • the computer 1 compares the received coordinate value (ie, the actual coordinate value) with the theoretical coordinate value stored in advance. If the same, it determines that the touch screen function circuit on the main board 2 is normal; otherwise, it determines that the touch screen function circuit is faulty.
  • the theoretical coordinate value of the point C can be calculated in advance.
  • resistors R1 and R2 with equal resistances and resistors R 3 and R4 with equal resistances can be selected to form two resistor series branches, or the resistances of the four resistors R 1 -R4 can be Set to equal.
  • test result screen of the normal or faulty operation of the touch screen function circuit is output through the computer display, and is provided to the operator for inspection.
  • the computer 1 outputs a low level test start command signal P1 through its data set card, and controls the transistors Q1 and Q2 to be turned off to stop detecting the touch screen function circuit on the main board 2.
  • Embodiment 2 In the test apparatus of this embodiment, a simulation for simulating a 4-wire resistive touch screen is mainly provided by four resistors R3013, R3014, R3015 and R3016 and two switch circuits K3001 and ⁇ 3002. Circuit, see Figure 7.
  • the analog circuit is connected to the ⁇ +, ⁇ -, ⁇ +, ⁇ -terminals of the 4-wire resistive touch screen on the main board of the mobile phone to test the touch screen function circuit on the mobile phone main board.
  • the resistor R3013 and the resistor R3014 may be connected in series and connected between the ⁇ + and X- terminals, and the resistor R3015 and the resistor R3016 may be connected in series and connected between the ⁇ + and ⁇ - terminals, and the two resistors are connected in series.
  • the intermediate nodes C are connected to each other; the switching paths of the two switching circuits ⁇ 3001 and ⁇ 3002 can be respectively connected between the resistor R3013 and the ⁇ + terminal and between the resistor R3014 and the X- terminal, as shown in FIG. 7, or respectively connected Between the resistor R3015 and the ⁇ + terminal and between the resistor R3016 and the ⁇ -terminal, the two switching circuits are controlled to conduct after the start of the test.
  • test fixture 3 for mounting the circuit board 2 to be tested and a test circuit board 4 connected to the test fixture 3 are also provided in the test device, see Figure 4 shows.
  • Four probes XI, ⁇ 0, ⁇ 1, and ⁇ are formed on the test fixture 3 for respectively connecting with the four terminals ⁇ +, ⁇ -, ⁇ +, ⁇ on the main board of the mobile phone.
  • the analog circuit is disposed on the test circuit board 4, and a resistor series branch formed by connecting resistors R3013 and R3014 in series is connected between the probes XI and X0; and another resistor series series branch formed by connecting resistors R3015 and R3016 in series Connected between probes ⁇ 1 and ⁇ 0.
  • the mobile phone motherboard can be used to sequentially apply a bias voltage to the two resistor series branches; then, respectively, the partial voltage values of the intermediate nodes C of the two resistor series branches are read; According to the two partial pressure values read, the coordinate values can be converted and recorded as actual coordinate values.
  • the theoretical coordinate value of the C point can be calculated in advance.
  • the actual coordinate value is compared with the theoretical coordinate value. If they are the same, it is considered that the touch screen function circuit on the mobile phone main board accurately obtains the coordinate information, and the touch screen function circuit is normal. On the contrary, if the obtained actual coordinate value is different from the theoretical coordinate value, it is considered that the touch screen function circuit cannot accurately acquire the coordinate information, and the touch screen function circuit is faulty.
  • the touch screen controller U1 on the main board of the mobile phone first applies a certain bias voltage to the ⁇ + terminal, such as the reference voltage VREF, and biases the X-terminal to 0V, and reads the ⁇ + or ⁇ -terminal.
  • the voltage value you can get a partial voltage value V x ; Then, stop applying a bias voltage between the X+ and X- terminals, and then apply a bias voltage to the Y+ terminal, such as the reference voltage VREF, and Y-
  • the terminal is biased to 0V, and the voltage value on the X+ or X- terminal is read to obtain another partial voltage value V Y .
  • V r ⁇ XR3014
  • V Y ⁇ XR3016.
  • the two partial voltage values V x and V Y are read by the touch screen controller U1, and after the ADC conversion is performed, the coordinate value of the generated C point can be calculated, which is equivalent to obtaining the coordinate value of the touch point on the touch screen. Comparing the coordinate value with the theoretical coordinate value, it can be determined whether the touch screen function circuit on the mobile phone main board is normal.
  • four non-zero resistors can be selected as the four resistors.
  • the amplitudes of the bias voltages VREF outputted through the X+ terminal and the Y+ terminal of the touch screen controller U1 are equal, it can be determined that the touch screen function circuit is normal as long as it is detected that the X coordinate and the Y coordinate of the received actual coordinate value are equal; , determine the touch screen function circuit failure.
  • zero resistance can also be used as the resistor R301 3 and the resistor R301 5 , while the resistor R3014 and the resistor R3016 are non-zero resistors, and the resistance values can be equal or different.
  • the two divided voltage values V x and V Y received through the touch screen controller U1 are equal to the magnitude of the bias voltage, it can be determined that the touch screen function circuit is normal; otherwise, the touch screen function circuit is determined to be faulty.
  • an actuator such as a display screen or an indicator light
  • the CPU on the motherboard of the mobile phone is connected, and the touch screen is used by the CPU.
  • the actual coordinate value fed back by the controller U1 is compared with the theoretical coordinate value. If they are the same, the control signal is output to the actuator, and the actuator is controlled to operate, for example, the screen for controlling the display screen to switch its display or the control indicator is lit, otherwise, the execution is performed.
  • the agency does not act and then gives clear instructions to the operator.
  • FIG. 4 shows.
  • 3 is a test fixture for mounting and fixing the mobile phone motherboard 2 (ie, the circuit board to be tested); 4 is a test circuit board on the test device, and the analog circuit for simulating the resistive touch screen is carried in On it.
  • the actual coordinate value fed back through the touch screen controller U1 is transmitted to the computer 1 via the CPU, and the computer 1 compares the actual coordinate value with the theoretical coordinate value to generate a test result, which is displayed on the display of the computer 1. , and then make clear instructions to the operator.
  • one or two relays can be used for circuit design, as shown in FIG. 7 Show.
  • the two normally open contacts of the relay can be used as the two switching paths of the switching circuit, which are respectively connected between the resistor R3013 and the X+ terminal and between the resistor R3014 and the X- terminal, or respectively connected. Between the resistor R3015 and the Y+ terminal and between the resistor R3016 and the Y- terminal.
  • the two relays K3001 and ⁇ 3002 are used for the switching circuit design, one of the two relays ⁇ 300 ⁇ 3002 can be used as the two switching paths of the switching circuit, which are respectively connected between the resistor R3013 and the ⁇ + terminal.
  • a manual switch When it is required to test the touch screen function circuit on the mobile phone main board, manually closing the manual switch, energizing the coils of the relays ⁇ 3001, ⁇ 3002, and absorbing the normally open contacts thereof, the mobile phone main board and the analog circuit can be realized. Connected.
  • the second is to connect one end of the relay ⁇ 3001, ⁇ 3002 coil to the DC power supply VCC, and the other end to the collector of an NPN type transistor Q3002 through the current limiting resistor R3012.
  • the emitter of the transistor Q3002 is grounded, and the base is passed through the resistor R3011.
  • the ground is connected to the DC power supply VCC via a resistor R3010, and the manual power switch is connected to the DC power supply VCC.
  • the third is that for the test device equipped with the computer 1, the second circuit design scheme can be slightly modified, the manual switch is removed, and a communication control line ctl is connected to the base of the transistor Q3002. Between the computers 1, in this embodiment, it can be specifically connected to the computer 1.
  • the data start port of the data collection card is received by the computer 1 to output a test start command signal ON/OFF, as shown in FIG.
  • the test start command signal is at a high level ON
  • the transistor Q 3002 is saturated and turned on, and the coils of the control relays K 3001 and ⁇ 3002 are energized, thereby absorbing the normally open contacts thereof, thereby realizing the mobile phone motherboard. Connected to the analog circuit.
  • control of the relay in this embodiment is not limited to the above examples.
  • the control circuit of the low-level circuit is turned off by the manual switch or the data of the computer 1 to output the low-level control signal OFF, so that the switch circuit of the switch circuit is disconnected, and the touch screen function circuit on the main board can be stopped. Detection.
  • the test method and the test device of the invention increase the analog circuit for the analog resistive touch screen on the basis of the existing mobile phone circuit board test device by simulating the internal resistance structure of the resistive touch screen, so as to detect the touch screen function circuit on the mobile phone main board.
  • the resistance changes and the corresponding coordinate information is generated. Therefore, in the process of functional testing the mobile phone motherboard, the performance detection of the touch screen function circuit on the mobile phone motherboard can be completed without plugging in the actual resistive touch screen, thereby simplifying the operation steps and reducing the test cost.
  • test method and the test device provided by the present invention are also applicable to the test of the circuit board circuit supporting the 4-wire resistive touch screen except the mobile phone main board, which is not specifically limited in this embodiment.

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  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
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  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

本发明公开了一种用于测试电路板上触摸屏功能电路的方法及装置，用于对支持4线式电阻式触摸屏的电路板进行测试，电路板上设置有端子X+、X-、Y+、Y-；在X+、X-两个端子之间串联两个电阻，在Y+、Y-两个端子之间串联另外两个电阻，并将两个电阻串联支路的中间节点连接在一起；通过电路板依次对两个电阻串联支路施加偏置电压，并分别读取两个电阻串联支路的中间节点的分压值，然后根据读取到的两个分压值判断电路板的触摸屏功能电路是否正常。本发明采用四个普通电阻代替实际的电阻式触摸屏对电路板进行检测，测试成本大大降低，不会对触摸屏造成损伤，并且消除了操作工人主观误判的可能性。

Description

用于测试电路板上触摸屏功能电路的方法及装置 技术领域
本发明属于电路板功能检测技术领域， 具体地说， 是涉及一种针对支持电 阻式触摸屏的电路板提出的用于对该电路板上的触摸屏功能电路进行检测的测 试方法及测试装置。
背景技术
伴随着手机产品在全球的快速普及， 手机的需求量不断增大， 且用户更换 手机的频率日渐加快， 为此， 手机的生产追求高效率的测试， 同时要求尽量减 少对操作工人的要求， 因此实现手机功能的自动化测试是当前手机生产的发展 趋势。 而在当今手机的 PCBA ( Pinter C i rcui t Board As sembly, 即已经装配 上各种电子器件的电路板）生产中，对于支持电阻式触摸屏的手机电路板来说， 其触摸屏功能电路的检测目前也只是通过给手机电路板接入实际的电阻式触摸 屏， 工人在触摸屏上操作 （比如点、 划等）检查手机在画面上的响应来验证手 机电路板上的触摸屏功能电路是否正常。 在实际测试过程中， 生产线体通常会 制作一些夹具， 即测试夹具， 将触摸屏安装在测试夹具上， 操作工人在进行电 路板检测前首先把触摸屏的 FPC连接器装入到手机电路板的 FPC连接器上， 然 后再把手机电路板放入测试夹具， 为手机电路板和触摸屏供电， 操作触摸屏对 手机电路板上的触摸屏功能电路进行检测。
现有的这种手机电路板测试方法主要存在以下缺点： 1、在每次测试手机电 路板的触摸屏功能电路前， 都需要操作工人将触摸屏与手机电路板连接好， 由 此增加了操作工人的劳动量； 2、在测试过程中， 需要操作工人主观判断电路板 的触摸屏功能电路是否运行正常， 即是否做出了正确的响应， 从而无法避免误 判问题， 缺少防呆措施； 3、 需要实际的触摸屏用于手机电路板的检测过程， 不 仅需要占用大量的触摸屏， 而且生产线体的测试同时会损耗掉许多触摸屏， 由 此也造成了测试成本的升高。 发明内容
本发明的目的在于提供一种用于测试电路板上触摸屏功能电路的方法， 釆 用该方法不再需要将实际的触摸屏应用到生产线体上即可完成对电路板上触摸 屏功能电路的测试任务， 且测试结果不再依赖操作工人的主观判断。
为解决上述技术问题， 本发明釆用以下技术方案予以实现：
一种用于测试电路板上触摸屏功能电路的方法， 所述电路板支持 4线式电 阻式触摸屏， 电路板上设置有用于连接电阻式触摸屏的四个端子 X+、 X-、 Y+、 Υ-; 在 Χ+、 X-两个端子之间串联两个电阻， 在 Υ+、 Υ -两个端子之间串联另外两 个电阻， 并将两个电阻串联支路的中间节点连接在一起； 通过电路板依次对两 个电阻串联支路施加偏置电压； 分别读取两个电阻串联支路的中间节点的分压 值； 根据读取到的两个分压值判断电路板的触摸屏功能电路是否正常。
进一步的， 所述电路板通过其触摸屏功能电路首先向 Χ+端子施加偏置电 压， 并将 X-端子偏置为 0V, 读取 Υ+或者 Υ-端子的电压值， 获得一个分压值； 然后向 Υ+端子施加偏置电压， 并将 Υ-端子偏置为 0V, 读取 Χ+或者 X-端子的电 压值， 获得另外一个分压值。
又进一步的， 所述根据读取到的两个分压值判断电路板的触摸屏功能电路 是否正常的具体过程可以釆用以下两种设计方式：
其一是， 利用触摸屏功能电路对接收到的分压值进行模数转换， 并生成坐 标值传输至电路板上的 CPU; 所述 CPU将坐标值反馈给计算机； 所述计算机将 接收到的坐标值与理论坐标值进行比较，若相同，则判定触摸屏功能电路正常， 并显示判定结果。
其二是， 利用触摸屏功能电路对接收到的分压值进行模数转换， 并生成坐 标值传输至电路板上的 CPU; 所述 CPU将坐标值与理论坐标值进行比较， 若相 同， 则判定触摸屏功能电路正常， 输出控制信号至执行机构， 控制执行机构动 作。通过观察执行机构动作与否， 即可清楚地判断出触摸屏功能电路是否正常。
优选的， 施加到所述两个电阻串联支路上的偏置电压的幅值相等， 且每一 个电阻串联支路中的两个电阻的阻值相等， 所述计算机在接收到坐标值后， 判 断 X坐标和 Y坐标的数值是否相等，若相等，则判定所述触摸屏功能电路正常。
当然，在所述的两个电阻串联支路中，也可以将连接 X+和 Y+端子的两个电 阻选用零电阻或者非零电阻； 而连接 X-和 Y-端子的两个电阻必须是非零电阻， 以保证测试的正常进行。
本发明同时又提供了一种用于测试电路板上触摸屏功能电路的装置， 用于 对支持 4线式电阻式触摸屏的电路板进行测试， 并且在所述电路板上设置有用 于连接电阻式触摸屏的四个端子 Χ+、 Χ-、 Υ+、 Υ-; 其中， 在所述装置中设置有 一用于模拟电阻式触摸屏的模拟电路， 在所述模拟电路中包含有四个电阻， 其 中两个电阻串联后连接在 Χ+、 X-端子之间， 另外两个电阻串联后连接在 Υ+、 Υ- 端子之间，且两个电阻串联支路的中间节点相交连接； 所述电路板通过 χ+、 χ-、 γ+、 γ-四个端子依次对所述的两个电阻串联支路施加偏置电压， 并分别读取两 个电阻串联支路的中间节点的分压值， 根据读取到的两个分压值判断电路板上 的触摸屏功能电路是否正常。
进一步的， 所述电路板利用其上的触摸屏控制器向 Χ+、 Χ-、 Υ+、 Υ-四个端 子依次施加偏置电压并接收分压值， 在对分压值进行模数转换后， 生成坐标值 传输至电路板上的 CPU;
所述 CPU连接计算机或者执行机构； 当与计算机连接时， 将坐标值反馈给 计算机， 计算机将接收到的坐标值与理论坐标值进行比较， 若相同， 则判定触 摸屏功能电路正常， 并显示判定结果； 当连接执行机构时， 所述 CPU将接收到 的坐标值与理论坐标值进行比较， 若相同， 则判定触摸屏功能电路正常， 输出 控制信号至执行机构， 控制执行机构动作， 进而通过观察执行机构动作与否， 来判断出触摸屏功能电路是否正常。
再进一步的， 在所述的模拟电路中， 所述的两个电阻串联支路各自通过一 个开关电路的开关通路分别与所述的 X+、 Y+端子——对应连接， 或者在其中一 个电阻串联支路的两端各自连接一个开关电路的开关通路， 并通过所述的开关 通路分别与 x+、 x-端子对应连接或者分别与 Υ+、 Υ-端子对应连接； 两个开关电 路在测试开始时受控导通， 具体可以利用计算机发出的测试开始指令信号控制 两个开关电路导通， 开始进行电路板的测试过程。
更进一步的， 在所述装置中还设置有用于安装所述电路板的测试夹具， 在 所述测试夹具上设置有用于与所述电路板上四个端子 Χ+、 Χ-、 Υ+、 Υ 对应 连接的四个探针， 所述模拟电路与所述的四个探针对应连接。
与现有技术相比， 本发明的优点和积极效果是： 本发明釆用四个普通电阻 代替实际的电阻式触摸屏用于对支持 4线式电阻式触摸屏的电路板进行检测， 由于测试过程无需再使用实际的电阻式触摸屏， 因此测试成本大大降低， 并且 可以避免对触摸屏造成损伤。 此外， 釆用本发明的测试方法及测试装置， 操作 工人无需在测试前将电路板与触摸屏连接， 由此减轻了操作工人的工作量。 并 且， 测试结果自动生成， 消除了操作工人主观误判的可能性。
结合附图阅读本发明实施方式的详细描述后， 本发明的其他特点和优点将 变得更加清楚。
附图说明
图 1是现有 4线式电阻式触摸屏的屏结构示意图；
图 2是检测现有 4线式电阻式触摸屏的触摸点位置的 X轴坐标的电路原理 图；
图 3是检测现有 4线式电阻式触摸屏的触摸点位置的 Υ轴坐标的电路原理 图；
图 4是本发明所提出的用于测试电路板上触摸屏功能电路的装置的一种实 施例的系统架构图；
图 5是图 4中电阻式触摸屏模拟电路的一种实施例的电路原理图； 图 6是图 4中计算机所运行的测试程序的一种实施例的流程图； 图 7是图 4中电阻式触摸屏模拟电路的另外一种实施例的电路原理图。 具体实施方式 下面结合附图对本发明的具体实施方式进行详细地描述。
目前的电阻式触摸屏，其外观类似显示屏幕，通过接触此屏幕的不同位置， 对外提供不同的电阻值， 从而使得屏幕上被触压的位置和电阻值相对应， 将其 作为输入设备， 便可直观地控制整机执行相应的处理操作。
下面以 4线式电阻式触摸屏为例， 首先对电阻式触摸屏的工作原理进行简 要介绍。
触摸式显示屏是将触摸屏附着在显示器的表面， 与显示器配合使用。 通过 触摸产生的模拟电信号被转换为数字信号后 , 由处理器计算出触摸点的坐标， 从而得到操作者的意图并进行响应。 目前， 4 线式电阻式触摸屏在实际应用中 使用较多， 这种触摸屏由 4层透明层构成： 最下面是基层， 通常由玻璃或者有 机玻璃制成； 最上面是塑料层， 经过硬化处理， 光滑防刮； 位于上下两层之间 的是两个金属导电层， 参见图 1所示， 这两层由细小的透明隔离点进行绝缘。 当手指触摸屏幕时， 两个导电层在触摸点处接触。
触摸屏的两个金属导电层分别用来测量 X轴和 Y轴方向的坐标， 其中一层 ( X层）在屏幕的左右边缘各布设有一条垂直总线， 记为 Χ+、 X-, 用于 X轴坐 标的测量， 如图 1所示； 另外一层（Y层）在屏幕的上下边缘各布设有一条水 平总线， 记为 Y+、 Υ-, 用于 Υ轴坐标的测量， 这就构成了 4线式电阻式触摸屏 的四条引线。 当在一对引线上施加电压时， 在该导电层上就会形成均勾连续的 电压分布。 若需要在 X轴方向上进行测量， 则可以将左侧总线 X-偏置为 0V, 右 侧总线 Χ+偏置为参考电压 VREF , 而在 Υ+、 Υ_两条总线之间不施加电压。 由此 一来，在 X平行电压场中，触摸点 Ρ处的电压值可以从 Υ+或者 Υ-引线上读取出 来， 如图 2所示。 同理， 若需要在 Υ轴方向上进行测量， 则可以将上方总线 Υ- 偏置为 0V, 下方总线 Υ+偏置为参考电压 VREF, 而在 Χ+、 X-两条总线之间不施 加电压。 由此， 在 Υ平行电压场中， 触摸点 Ρ处的电压值可以从 Χ+或者 X-引线 上读取出来， 如图 3所示。 通过读取上述的两个电压值， 并进行 ADC转换， 即 可获得触摸点 Ρ的 X轴方向和 Υ轴方向的坐标值。 在目前支持 4线式电阻式触摸屏的手机电路板上， 其触摸屏功能电路通常 包含有一个触摸屏控制器， 或者在手机的 CPU中集成触摸屏控制器的功能。 所 述触摸屏控制器负责对触摸屏的四条引线进行电压偏置， 并釆集 X轴方向和 Y 轴方向的电压值， 进行 ADC转换后， 将模拟量转换成数字量， 从而得到触摸点 在触摸屏上的坐标值。 所述触摸屏控制器将得到的坐标值传输给手机的 CPU , CPU根据坐标值的变化改变显示屏的画面， 从而实现了手机对触摸屏操作的响 应。
本发明针对目前 4线式电阻式触摸屏的上述特性， 对用于测试电路板电路 的功能检测自动化测试设备进行改进性设计， 使其在不需要电路板连接实际触 摸屏的前提下， 完成对电路板上触摸屏功能电路的性能检测。
下面以手机主板作为待测试的电路板为例， 通过两个具体的实施例来详细 阐述对待测试电路板上的触摸屏功能电路进行测试的方法及装置。
实施例一， 在本实施例的测试装置中主要设置有一个由四个电阻 Rl、 R2、 R3和 R4连接而成的用于模拟 4线式电阻式触摸屏的模拟电路，参见图 5所示。 将所述模拟电路与手机主板上用于连接 4线式电阻式触摸屏的 X+、 X-、 Y+、 Υ- 端子相连接， 即可对手机主板上的触摸屏功能电路进行测试。
具体来讲， 可以将其中两个电阻 Rl、 R2串联后， 构成一个电阻串联支路， 连接在 X+、 X-端子之间； 将另外两个电阻 R3、 R4 串联后， 构成第二个电阻串 联支路， 连接在 Υ+、 Υ-端子之间； 然后将两个电阻串联支路的中间节点 C连接 在一起。
为了方便测试装置与手机主板的连接， 并方便进行手机主板的功能测试， 在测试装置中还设置有计算机 1、用于安装待测电路板 2 (即本实施例中的手机 主板） 的测试夹具 3以及与所述测试夹具 3相连接的测试电路板 4 , 参见图 4 所示。 在测试夹具 3上制作有四个探针 XI、 Χ0、 Υ1、 ΥΟ , 分别用于与手机主板 上的四个端子 Χ+、 Χ-、 Υ+、 Υ 对应连接。 将所述模拟电路布设在测试电路 板 4上， 并且将由电阻 Rl、 R2串联构成的电阻串联支路连接在探针 XI、 X0之 间； 将由电阻 R3、 R4串联构成的第二个电阻串联支路连接在探针 Yl、 Υ0之间。 在对手机主板上的触摸屏功能电路进行测试时， 可以利用手机主板依次向两个 电阻串联支路施加偏置电压， 比如可以首先在主板的 Χ+、 X-端子之间施加一定 的偏置电压， 而 Υ+、 Υ-端子之间不施加电压， 此时， 可以通过读取 Υ+端子或者 Υ-端子上的电压值来获得电阻 Rl、 R2串联支路的中间节点处 C的分压值。然后， 停止在 Χ+、 X-端子之间施加电压， 而转由向 Υ+、 Υ-端子之间施加一定的偏置电 压， 此时， 可以通过读取 Χ+端子或者 X-端子上的电压值来获得电阻 R3、 R4串 联支路的中间节点处 C的分压值。 根据读取到的两个分压值， 即可换算出坐标 值， 记为实际坐标值。 由于通过主板施加到两个电阻串联支路上的偏置电压以 及四个电阻 R1-R4的阻值是可以事先获知的， 因此可以预先计算出 C点的理论 坐标值。 将实际坐标值与理论坐标值进行比较， 若相同， 则认为主板上的触摸 屏功能电路准确获得了坐标信息， 触摸屏功能电路正常。 反之， 若通过触摸屏 功能电路反馈的实际坐标值与理论坐标值不同， 则认为所述触摸屏功能电路不 能准确地获取坐标信息， 触摸屏功能电路故障。 由此， 在手机主板的测试过程 中， 无需在电路板上连接实际的触摸屏即可对其上的触摸屏功能电路的性能进 行准确地检测， 从而简化了测试工作， 降低了测试成本。 此外， 对于传统的测 试技术来说， 由于在进行主板测试时需要连接实际的触摸屏， 这样就容易出现 由于触摸屏自身的问题而导致对主板电路的状态产生误判的问题出现。 而釆用 本实施例的测试技术后， 可以很好地避免此类问题的发生， 提高了测试的准确 性。
为了对触摸屏功能电路的测试起止时刻进行控制， 本实施例优选在所述测 试电路板 4上的两个电阻串联支路上再各自连接一个开关电路， 将两个开关电 路的开关通路分别对应连接在探针 XI、 Y1与两个电阻串联支路之间，控制端接 收计算机输出的测试开始指令信号 P1 ,在开始对主板上的触摸屏功能电路进行 测试时， 输出有效的测试开始指令信号 P1 , 控制两路开关电路导通， 进而实现 两个电阻串联支路在两对探针 X1 /X0、 Y1 /Y0之间的连通。 作为一种优选设计方案，本实施例釆用两个 NPN型三极管 Ql、 Q2来设计所 述的开关电路， 参见图 5所示。 将三极管 Q1的集电极连接到探针 XI上， 发射 极连接电阻 R1 ,进而通过电阻 R2连接探针 X0;将三极管 Q2的集电极连接到探 针 Y1上， 发射极连接电阻 R3 , 进而通过电阻 R4连接探针 Y0; 两个三极管 Ql、 Q2的基极通过通信控制线 ct l连接计算机，接收计算机中的数据釆集卡发出的 测试开始指令信号 P1 , 并在所述测试开始指令信号 P1为高电平时饱和导通， 连通两对探针 X1/X0、 Y1/Y0之间的电阻串联支路，开始进行触摸屏功能电路的 检测。
当然， 所述开关电路也可以釆用可控硅、 M0S 管等其他具有开关作用的元 器件进行电路设计， 本实施例并不仅限于以上举例。
下面结合图 6对本实施例的测试方法进行具体描述。
首先， 将待测试的手机主板 2安装到测试夹具 3上， 如图 4所示， 将测试 夹具 3闭合， 使夹具上的四个探针 XI、 Χ0、 Υ1、 Υ0刚好与手机主板 2上的用于 连接电阻式触摸屏的四个端子 Χ+、 Χ-、 Υ+、 Υ0对应连接上。 釆用一条通信控制 线 c 11连接在测试电路板 4与计算机 1之间， 在本实施例中可以具体连接到计 算机 1中数据釆集卡的一路数据输出端口上， 以接收计算机 1输出的测试开始 指令信号 Pl。 在手机主板 2与计算机 1主机之间釆用通信数据线 da ta进行连 接， 实现二者之间数据的双向通信。 由此， 便完成了硬件连接工作。
然后， 进入对手机主板 2上的触摸屏功能电路进行测试的进程， 参见图 6 所示， 包括以下过程：
S60 操作人员通过计算机 1输入启动测试的指令， 计算机 1在接收到启 动指令后， 通过其数据釆集卡输出有效的测试开始指令信号 P1 , 经由通信控制 线 c 11传输至测试电路板 4。
S602、测试电路板 4将接收到的测试开始指令信号 P1传输至 NPN型三极管 Ql、 Q2的基极， 控制三极管 Ql、 Q2饱和导通， 将电阻 Rl、 R2串联在探针 XI、 X0之间， 将电阻 R3、 R4 串联在探针 Yl、 Υ0之间。 由于探针 XI、 Χ0、 Yl、 ΥΟ 与手机主板 2上的端子 X+、 Χ_、 Υ+、 Υ0对应连接， 而四个端子 Χ+、 Χ_、 Υ+、 Υ0在手机主板 1上刚好与触摸屏功能电路（具体可以指触摸屏控制器 U1 )的相 应管脚对应连接， 因此，可以实现触摸屏控制器 U1对中间节点 C处分压值的检 测， 如图 5所示。
5603、计算机 1通过通信数据线 da ta与手机主板 1建立通讯链接，向手机 主板 2发送反馈触摸屏坐标值的请求。
根据触摸控制器 U1的工作原理：触摸屏控制器 U1实时地施加一定的偏置电 压到 X+端子， 在触摸屏没有被触摸时， 由于 X层与 Y层没有接触， 因此 Y+端子上 是没有电压的， 触摸屏控制器 U1认为此时触摸屏未被触摸； 而当触摸屏控制器 U1—旦检测到其 Y+端子上有电压时， 则认为触摸屏被触摸了， 此时触摸屏控制 器 U1 开始依次向 X+、 Y+端子施加偏置电压。 具体来讲， 所述触摸屏控制器 U1 首先向 X+端子施加一定的偏置电压，比如参考电压 VREF ,并将 X-端子偏置为 0V, 读取 Y+或者 Y-端子上的电压值， 即可获得一个分压值 Vx; 然后， 停止在 X+、 X- 端子之间施加偏置电压，转为向 Y+端子施加偏置电压， 比如也为参考电压 VREF, 并将 Y-端子偏置为 0V, 读取 X+或者 X-端子上的电压值， 即可获得另外一个分压 值 VY。 由图 5所示的电路可知：
V = x R2 ;
RI + R2
VY = xR4 ;
R3 + R4
触摸屏控制器 Ul 将读取到的两个分压值 Vx、 VY进行 ADC转换， 即可计算生成 C点 的坐标值， 即得到了触摸点在触摸屏上的坐标值。
5604、 触摸屏控制器 Ul 将生成的坐标值通过 I2C总线传输至手机主板 1上 的 CPU, CPU通过通信数据线 da ta与计算机 1通信， 将坐标值反馈给计算机 1。
5605、 计算机 1将接收到的坐标值（即实际坐标值）与其内部事先存储的 理论坐标值进行比较， 若相同， 则判定主板 2上的触摸屏功能电路正常； 否则， 判定触摸屏功能电路故障。 在本实施例中， 由于通过触摸屏控制器 U1施加的偏置电压 VREF以及四个 电阻 R1-R4的阻值可以事先获得， 因此， 可以预先计算出 C点的理论坐标值。 作为一种优选的设计方案，可以选择阻值相等的电阻 Rl、 R2以及阻值相等的电 阻 R 3、 R4组成两个电阻串联支路，也可以将四个电阻 R 1 -R4的阻值均设为相等。 当通过触摸屏控制器 U1的 X+端子和 Y+端子输出的偏置电压 VREF的幅值相等 时， 只要计算机 1检测出接收到的实际坐标值的 X坐标和 Y坐标相等， 则可判 定触摸屏功能电路正常； 否则， 判定触摸屏功能电路故障。
5606、 通过计算机 1输出测试结果。
即通过计算机显示器输出触摸屏功能电路正常或者故障的测试结果画面， 提供给操作工人查阅。
5607、 测试结束， 计算机 1通过其数据釆集卡输出低电平的测试开始指令 信号 P1 , 控制三极管 Ql、 Q2截止， 停止对主板 2上的触摸屏功能电路进行检 测。
实施例二， 在本实施例的测试装置中主要设置有一个由四个电阻 R3013、 R3014、 R3015和 R3016和两个开关电路 K3001、 Κ3002连接而成的用于模拟 4 线式电阻式触摸屏的模拟电路， 参见图 7所示。 将所述模拟电路连接在手机主 板上用于连接 4线式电阻式触摸屏的 Χ+、 Χ-、 Υ+、 Υ-端子之间， 即可对手机主 板上的触摸屏功能电路进行测试。
具体来讲，可以将电阻 R3013与电阻 R3014串联后连接在 Χ+、 X-端子之间， 将电阻 R3015与电阻 R3016串联后连接在 Υ+、 Υ-端子之间， 且两个电阻串联支 路的中间节点 C相交连接； 两个开关电路 Κ3001、 Κ3002的开关通路可以选择分 别连接在电阻 R3013与 Χ+端子之间以及电阻 R3014与 X-端子之间，如图 7所示， 或者分别连接在电阻 R3015与 Υ+端子之间以及电阻 R3016与 Υ-端子之间，两个 开关电路在测试开始后受控导通。
为了方便测试装置与手机主板的连接， 在测试装置中还设置有用于安装待 测电路板 2的测试夹具 3以及与所述测试夹具 3相连接的测试电路板 4 , 参见 图 4所示。 在测试夹具 3上制作有四个探针 XI、 Χ0、 Υ1、 ΥΟ, 分别用于与手机 主板上的四个端子 Χ+、 Χ-、 Υ+、 Υ 对应连接。 将所述模拟电路布设在测试 电路板 4上，并且将由电阻 R3013、 R3014串联构成的电阻串联支路连接在探针 XI、 X0之间； 将由电阻 R3015、 R3016 串联构成的另外一个电阻串联支路连接 在探针 Υ1、 Υ0之间。在对手机主板上的触摸屏功能电路进行测试时， 可以利用 手机主板依次向两个电阻串联支路施加偏置电压； 然后分别读取两个电阻串联 支路的中间节点 C的分压值；进而根据读取到的两个分压值即可换算出坐标值， 记为实际坐标值。 由于通过手机主板施加到两个电阻串联支路上的偏置电压以 及四个电阻 R3013-R3016的阻值都是可以事先获知的， 因此可以预先计算出 C 点的理论坐标值。 将实际坐标值与理论坐标值进行比较， 若相同， 则认为手机 主板上的触摸屏功能电路准确获得了坐标信息， 触摸屏功能电路正常。 反之， 若获得的实际坐标值与理论坐标值不同， 则认为所述触摸屏功能电路不能准确 地获取坐标信息， 触摸屏功能电路故障。
举例说明：假设通过手机主板上的触摸屏控制器 U1首先向 Χ+端子施加一定 的偏置电压， 比如参考电压 VREF, 并将 X-端子偏置为 0V, 读取 Υ+或者 Υ-端子上 的电压值， 即可获得一个分压值 Vx; 然后， 停止在 X+、 X-端子之间施加偏置电 压， 转为向 Y+端子施加偏置电压， 比如也为参考电压 VREF, 并将 Y-端子偏置为 0V, 读取 X+或者 X-端子上的电压值， 即可获得另外一个分压值 VY。 由图 4所示 的电路可知：
Vr = ^ XR3014；
R3013 + R3014
VY = ^ XR3016。
R3015 + R3016
利用触摸屏控制器 U1读取这两个分压值 Vx、 VY, 进行 ADC转换后， 即可计算生成 C点的坐标值，相当于得到了触摸点在触摸屏上的坐标值。将所述坐标值与理论 坐标值进行比较， 即可判断出手机主板上的触摸屏功能电路是否正常。
作为一种优选的设计方案， 可以选择四个非零电阻作为所述的四个电阻 R301 3-R3016 , 且电阻 R301 3、 R 3014的阻值相等， 电阻 R3015、 R3016的阻值相 等， 由此组成两个电阻串联支路， 也可以将四个电阻 R301 3-R3016的阻值设为 相等。当通过触摸屏控制器 U1的 X+端子和 Y+端子输出的偏置电压 VREF的幅值 相等时， 只要检测出接收到的实际坐标值的 X坐标和 Y坐标相等， 则可判定触 摸屏功能电路正常； 否则， 判定触摸屏功能电路故障。
当然， 也可以选用零电阻作为电阻 R301 3和电阻 R301 5 , 而电阻 R3014和电 阻 R3016 则选用非零电阻， 阻值可以相等也可以不等。 此时， 当通过触摸屏控 制器 U1 接收到的两个分压值 Vx、 VY均等于偏置电压的幅值时， 即可判定触摸屏 功能电路正常； 否则， 判定触摸屏功能电路故障。
为了使操作工人能够清楚的掌握测试结果， 可以在本实施例的测试装置中 进一步设置执行机构， 例如显示屏或者指示灯等， 如图 7所示， 连接手机主板 上的 CPU ,利用 CPU对触摸屏控制器 U1反馈的实际坐标值与理论坐标值进行比 较， 若相同， 则输出控制信号至执行机构， 控制执行机构动作， 例如控制显示 屏切换其显示的画面或者控制指示灯点亮， 否则， 执行机构不动作， 进而向操 作工人做出清楚的指示。
当然， 也可以釆用在测试装置中配置计算机 1 , 利用通信数据线 da ta连接 计算机 1与手机主板，具体可连接手机主板上的 CPU , 实现手机主板与计算机 1 之间数据的双向通信， 参见图 4所示。 图 4中， 3为测试夹具， 用于安装和固 定所述的手机主板 2 (即待测电路板）； 4为测试装置上的测试电路板， 用于模 拟电阻式触摸屏的模拟电路即承载在其上。 在对手机主板 2进行测试时， 通过 触摸屏控制器 U1反馈的实际坐标值经由 CPU传输至计算机 1 ,计算机 1将实际 坐标值与理论坐标值进行比较， 以产生测试结果， 显示在计算机 1的显示器， 进而向操作工人做出清楚的指示。
当然， 对于如何产生测试结果还有很多种实现方式， 本实施例并不仅限于 以上举例。
对于所述开关电路可以釆用一个或者两个继电器进行电路设计， 如图 7所 示。 当釆用一个继电器时， 可以使用该继电器的两路常开触点作为开关电路的 两个开关通路，分别连接在电阻 R3013与 X+端子之间以及电阻 R3014与 X-端子 之间，或者分别连接在电阻 R3015与 Y+端子之间以及电阻 R3016与 Y-端子之间。 当釆用两个继电器 K3001、 Κ3002 进行开关电路设计时， 可以使用两个继电器 Κ300 Κ3002中的各自一路常开触点作为开关电路的两个开关通路， 分别连接 在电阻 R3013与 Χ+端子之间以及电阻 R3014与 X-端子之间 （如图 7所示）， 或 者分别连接在电阻 R3015与 Υ+端子之间以及电阻 R3016与 Υ-端子之间。在测试 开始时， 通过控制所述继电器的线圈通电， 即可吸合其两路常开触点， 进入测 试过程。
对于所述继电器的通断电控制， 可以釆用多种设计方案， 以下列举三种设 计方式：
其一是，将继电器 Κ3001、 Κ3002线圈的一端通过一手动开关连接直流电源 VCC, 另一端接地。 当需要对手机主板上的触摸屏功能电路进行测试时， 手动闭 合所述的手动开关， 使继电器 Κ3001、 Κ3002的线圈通电， 吸合其常开触点， 即 可实现手机主板与所述模拟电路的连通。
其二是， 将继电器 Κ3001、 Κ3002线圈的一端连接直流电源 VCC, 另一端通 过限流电阻 R3012连接一颗 NPN型三极管 Q3002的集电极， 所述三极管 Q3002 的发射极接地， 基极通过电阻 R3011 —方面经由电阻 R3010接地， 另一方面通 过手动开关连接直流电源 VCC, 参见图 7所示。 当需要对手机主板上的触摸屏 功能电路进行测试时， 手动闭合所述的手动开关， 使三极管 Q3002饱和导通， 进而将继电器 K3001、 Κ3002线圈的另一端接地， 连通继电器 Κ3001、 Κ3002线 圈的供电回路， 使其常开触点吸合， 由此便实现了手机主板与所述模拟电路的 连通。
其三是， 对于配置有计算机 1的测试装置来说， 可以在上述第二种电路设 计方案的基础上略加改动， 去掉手动开关， 釆用一条通信控制线 c t l连接在三 极管 Q3002的基极与计算机 1之间， 在本实施例中可以具体连接到计算机 1中 数据釆集卡的一路数据输出端口上， 以接收计算机 1输出的测试开始指令信号 ON/OFF , 参见图 7所述。 当所述测试开始指令信号为高电平 ON时， 所述三极管 Q 3002饱和导通，控制继电器 K 3001、 Κ 3002的线圈通电，进而吸合其常开触点， 由此便可实现手机主板与所述模拟电路的连通。
当然， 本实施例对继电器的控制并不仅限于以上举例。
在手机主板的测试结束后， 通过断开手动开关或者通过计算机 1的数据釆 集卡输出低电平的控制信号 OFF , 使开关电路的开关通路断开， 即可停止对主 板上的触摸屏功能电路的检测。
本发明的测试方法和测试装置通过模拟电阻式触摸屏的内部电阻结构， 在 现有手机电路板测试装置的基础上增加用于模拟电阻式触摸屏的模拟电路， 来 使手机主板上的触摸屏功能电路检测阻值变化， 生成相应的坐标信息。 由此， 在对手机主板进行功能测试的过程中， 无需插接实际的电阻式触摸屏即可完成 对手机主板上触摸屏功能电路的性能检测， 由此简化了操作步骤， 降低了测试 成本。
当然， 本发明所提出的测试方法及测试装置也同样适用于除手机主板以外 的其他支持 4线式电阻式触摸屏的电路板电路的测试中， 本实施例对此不进行 具体限制。
应当指出的是， 以上所述仅是本发明的一种优选实施方式， 对于本技术领 域的普通技术人员来说， 在不脱离本发明原理的前提下， 还可以做出若干改进 和润饰， 这些改进和润饰也应视为本发明的保护范围。

Claims

权 利 要 求 书
1、一种用于测试电路板上触摸屏功能电路的方法，所述电路板支持 4线式 电阻式触摸屏， 电路板上设置有用于连接电阻式触摸屏的四个端子 X+、 X-、 Y+、 Υ-; 其特征在于：
在 Χ+、 X -两个端子之间串联两个电阻， 在 Υ+、 Υ -两个端子之间串联另外两 个电阻， 并将两个电阻串联支路的中间节点连接在一起；
通过电路板依次对两个电阻串联支路施加偏置电压；
分别读取两个电阻串联支路的中间节点的分压值；
根据读取到的两个分压值判断电路板的触摸屏功能电路是否正常。
2、根据权利要求 1所述的方法， 其特征在于： 所述通过电路板依次对两个 电阻串联支路施加偏置电压的具体过程为：
电路板通过其触摸屏功能电路首先向 Χ+端子施加偏置电压，并将 X-端子偏 置为 0V, 读取 Υ+或者 Υ-端子的电压值， 获得一个分压值； 然后向 Υ+端子施加 偏置电压， 并将 Υ-端子偏置为 0V, 读取 Χ+或者 X-端子的电压值， 获得另外一 个分压值。
3、根据权利要求 1所述的方法， 其特征在于： 所述根据读取到的两个分压 值判断电路板的触摸屏功能电路是否正常的具体过程为：
触摸屏功能电路对接收到的分压值进行模数转换， 并生成坐标值传输至电 路板上的 CPU;
所述 CPU将坐标值反馈给计算机；
所述计算机将接收到的坐标值与理论坐标值进行比较， 若相同， 则判定触 摸屏功能电路正常， 并显示判定结果。
4、根据权利要求 1所述的方法， 其特征在于： 所述根据读取到的两个分压 值判断电路板的触摸屏功能电路是否正常的具体过程为：
触摸屏功能电路对接收到的分压值进行模数转换， 并生成坐标值传输至电 路板上的 CPU;
所述 CPU将坐标值与理论坐标值进行比较， 若相同， 则判定触摸屏功能电 路正常， 输出控制信号至执行机构， 控制执行机构动作。
5、根据权利要求 3或 4所述的方法， 其特征在于： 在所述通过电路板依次 对两个电阻串联支路施加偏置电压的过程中， 施加到所述两个电阻串联支路上 的偏置电压的幅值相等， 且每一个电阻串联支路中的两个电阻的阻值相等； 所 述计算机在接收到坐标值后， 判断 X坐标和 Y坐标的数值是否相等， 若相等， 则判定所述触摸屏功能电路正常。
6、根据权利要求 1至 4中任一项所述的方法， 其特征在于： 在所述的两个 电阻串联支路中， 连接 X+和 Y+端子的两个电阻为零电阻或者非零电阻； 连接 X-和 Y-端子的两个电阻为非零电阻。
7、一种用于测试电路板上触摸屏功能电路的装置，用于对支持 4线式电阻 式触摸屏的电路板进行测试， 并且在所述电路板上设置有用于连接电阻式触摸 屏的四个端子 Χ+、 Χ-、 Υ+、 Υ-; 其特征在于： 在所述装置中设置有一用于模拟 电阻式触摸屏的模拟电路， 在所述模拟电路中包含有四个电阻， 其中两个电阻 串联后连接在 Χ+、 X-端子之间， 另外两个电阻串联后连接在 Υ+、 Υ-端子之间， 且两个电阻串联支路的中间节点相交连接； 所述电路板通过 Χ+、 Χ-、 Υ+、 Υ -四 个端子依次对所述的两个电阻串联支路施加偏置电压， 并分别读取两个电阻串 联支路的中间节点的分压值， 根据读取到的两个分压值判断电路板上的触摸屏 功能电路是否正常。
8、 根据权利要求 7 所述的装置， 其特征在于： 所述电路板利用其上的触 摸屏控制器向 Χ+、 Χ-、 Υ+、 Υ-四个端子依次施加偏置电压并接收分压值， 在对 分压值进行模数转换后， 生成坐标值传输至电路板上的 CPU;
所述 CPU连接计算机或者执行机构； 当与计算机连接时， 将坐标值反馈给 计算机， 计算机将接收到的坐标值与理论坐标值进行比较， 若相同， 则判定触 摸屏功能电路正常， 并显示判定结果； 当连接执行机构时， 所述 CPU将接收到 的坐标值与理论坐标值进行比较， 若相同， 则判定触摸屏功能电路正常， 输出 控制信号至执行机构， 控制执行机构动作。
9、 根据权利要求 8 所述的装置， 其特征在于： 在所述的模拟电路中， 所 述的两个电阻串联支路各自通过一个开关电路的开关通路分别与所述的 X+、 Y+ 端子——对应连接， 或者在其中一个电阻串联支路的两端各自连接一个开关电 路的开关通路， 并通过所述的开关通路分别与 X+、 X-端子对应连接或者分别与 Υ+、 Υ-端子对应连接； 两个开关电路在测试开始时受控导通。
10、 根据权利要求 7至 9中任一项所述的装置， 其特征在于： 在所述装置 中还设置有用于安装所述电路板的测试夹具， 在所述测试夹具上设置有用于与 所述电路板上四个端子 Χ+、 Χ_、 Υ+、 Υ 对应连接的四个探针， 所述模拟电 路与所述的四个探针对应连接。
PCT/CN2012/074065 2011-04-19 2012-04-16 用于测试电路板上触摸屏功能电路的方法及装置 WO2012142928A1 (zh)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN200986700Y (zh) * 2006-10-26 2007-12-05 比亚迪股份有限公司 一种四线制电阻式触摸屏测试电路
CN101846712A (zh) * 2010-04-01 2010-09-29 苏州崴展电子科技有限公司 电容式触摸屏ito电气特性检测方法及检测系统
CN102288894A (zh) * 2011-04-19 2011-12-21 青岛海信移动通信技术股份有限公司 用于测试主板上触摸屏功能电路的方法及装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN200986700Y (zh) * 2006-10-26 2007-12-05 比亚迪股份有限公司 一种四线制电阻式触摸屏测试电路
CN101846712A (zh) * 2010-04-01 2010-09-29 苏州崴展电子科技有限公司 电容式触摸屏ito电气特性检测方法及检测系统
CN102288894A (zh) * 2011-04-19 2011-12-21 青岛海信移动通信技术股份有限公司 用于测试主板上触摸屏功能电路的方法及装置

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