Pin detection circuit of circuit board of display device and pin detection method

Abstract

The present application provides an embodiment belonging to the field of circuit testing technology, and provides a pin detection circuit of a circuit board of a display device, and a pin detection method. In the pin detection device, the control circuit is configured to test multiple pins to be tested, the voltage conversion component is configured to convert the input voltage of the external power supply into a positive preset voltage, the charge pump component is configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage, the voltage selection component is configured to select the positive preset voltage or the negative preset voltage, the multi-channel switch component is configured to select the target pin among multiple pins to be tested, and the control circuit is configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain a test result. The present application implements the test of positive voltage and negative voltage on the pin to be tested through the charge pump, the test method is relatively simple, and the accuracy of the detection quality of the pin to be tested is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of circuit testing, and more specifically, to a pin detection circuit and a pin detection method for a circuit board of a display device. Background Art

[0002] During the production process of television circuit boards, multiple product tests are required to ensure that the quality of the circuit boards meets the requirements. The open circuit and short circuit measurement of the circuit boards is the basic test of circuit testing. When the welding quality of the circuit boards is abnormal, it is easy to cause open circuits or short circuits in the circuit boards.

[0003] At present, in the measurement of television circuit boards, including the measurement of the welding quality of circuit boards, an external display device and corresponding image and audio acquisition equipment can usually be connected to judge the output image of the circuit board to be tested, so as to determine the welding quality of the signal input link, signal processing module and signal output link of the circuit board.

[0004] However, the above test method has a relatively complicated process and the detection accuracy of welding quality is low. Summary of the invention

[0005] The embodiments of the present application provide a pin detection circuit and a pin detection method for a circuit board of a display device, which can be used to solve the problem in the related art that the pin detection process of the circuit board of the display device is relatively heavy and the detection accuracy of the welding quality is low.

[0006] In a first aspect, an embodiment of the present application provides a pin detection device for a circuit board of a display device, the pin detection device comprising:

[0007] A control circuit is connected to a plurality of pins to be tested of a circuit board to be tested and is configured to test the plurality of pins to be tested;

[0008] A voltage conversion component, connected to an external power source, and configured to convert an input voltage of the external power source into a positive preset voltage;

[0009] a charge pump component connected to the voltage conversion component and configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage;

[0010] A voltage selection component, connected to the charge pump component and the voltage conversion component respectively, and configured to sequentially select the positive preset voltage and the negative preset voltage, or sequentially select the negative preset voltage and the positive preset voltage;

[0011] a multi-channel switch component connected to the control circuit and the multi-channel switch component, and configured to select a target pin among the plurality of pins to be tested;

[0012] The control circuit is configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain a test result.

[0013] In this embodiment, the pin detection device includes a control circuit, a voltage conversion component, a charge pump component, a voltage selection component and a multi-channel switch component, the control circuit is connected to a plurality of pins to be tested of a circuit board to be tested, the voltage conversion component is connected to an external power supply, the charge pump component is connected to the voltage conversion component, the voltage selection component is respectively connected to the charge pump component, the voltage conversion component and the multi-channel switch component, and the multi-channel switch component is connected to the control circuit. Wherein, the control circuit is configured to test a plurality of pins to be tested, the voltage conversion component is configured to convert the input voltage of the external power supply into a positive preset voltage, the charge pump component is configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage, the voltage selection component is configured to sequentially select the positive preset voltage and the negative preset voltage, or sequentially select the negative preset voltage and the positive preset voltage, the multi-channel switch component is configured to select the target pin among a plurality of pins to be tested, and the control circuit is specifically configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain the test result. The present application implements positive voltage and negative voltage testing on the pin to be tested through a charge pump. The testing method is relatively simple and improves the accuracy of the detection quality of the pin to be tested.

[0014] In some embodiments of the present application, the control circuit includes:

[0015] A plurality of matching resistors are respectively connected to the plurality of pins to be tested through a plurality of first connecting wires;

[0016] A plurality of analog-to-digital conversion components connected to the plurality of first connecting lines, for any one of the analog-to-digital conversion components, is configured to measure a voltage value of a pin to be tested connected to the analog-to-digital conversion component;

[0017] The controller is connected to the multiple analog-to-digital conversion components and is configured to obtain voltage values ​​sent by the multiple analog-to-digital conversion components and determine whether the multiple pins to be tested are short-circuited or open-circuited based on the voltage values ​​sent by the multiple analog-to-digital conversion components.

[0018] In this embodiment, through the control circuit of this embodiment, the voltage of each pin can be tested to determine whether each pin is open or short-circuited, wherein the matching resistor can limit the output current of the charge pump to ensure that the current is within the specifications of the circuit board to be tested.

[0019] In some embodiments of the present application, the controller is configured as follows:

[0020] Acquire voltage values ​​of a plurality of second pins near the target pin;

[0021] It is determined whether the target pin has a continuous weld according to the voltage values ​​of the plurality of second pins.

[0022] In this embodiment, when determining the voltage value corresponding to the target pin, the voltage value of the pin near the target pin can be obtained to determine whether the target pin is connected.

[0023] In some embodiments of the present application, the analog-to-digital conversion component corresponding to the target pin and the analog-to-digital conversion component corresponding to the second pin are the same analog-to-digital conversion component.

[0024] In an embodiment of the present application, the target pin can be connected to multiple second pins in the same analog-to-digital conversion component, so that the voltage value of the second pin can be obtained at the same time when the voltage value of the target pin is obtained.

[0025] In some embodiments of the present application, the controller is configured as follows:

[0026] If, among the voltage values ​​of the plurality of second pins, there is a first voltage value that is the same as the voltage value of the target pin, it is determined that the target pin is soldered to the second pin corresponding to the first voltage value.

[0027] In this embodiment, when the voltage values ​​are the same, it can be determined that there is a solder joint on the target pin.

[0028] In some embodiments of the present application, for any pin to be tested, the pin to be tested is connected to a first diode and a second diode, the first diode is connected to a power supply, and the second diode is grounded;

[0029] When the voltage selection component selects the positive preset voltage, the control circuit is configured to: determine a first conduction voltage of the first diode to determine whether the pin to be tested is short-circuited or open-circuited according to the first conduction voltage;

[0030] If the voltage selection component selects the negative preset voltage, the control circuit is configured to: determine a second conduction voltage of the second diode to determine whether the pin to be tested is short-circuited or open-circuited according to the second conduction voltage.

[0031] In this embodiment, the positive preset voltage and the negative preset voltage are respectively selected to test the ground protection diode and the power protection diode of the pin to determine whether the pin to be tested is open or short.

[0032] In some embodiments of the present application, the multi-channel switch component is configured as follows:

[0033] Acquire a test instruction, wherein the test instruction is used to instruct to select the target pin among the plurality of pins to be tested;

[0034] According to the test instruction, the target pin is enabled.

[0035] In this embodiment, the multi-channel switch component obtains a test instruction to determine the target pin to be enabled.

[0036] In some embodiments of the present application, the charge pump component includes a first capacitor, a second capacitor, a third capacitor, a first switch, a second switch, a third switch and a fourth switch;

[0037] The first end of the first capacitor is connected to the first end of the first switch, the first end of the first switch is connected to the voltage conversion component, and the second end of the first capacitor is grounded;

[0038] The first end of the second switch is connected to the second end of the first switch, and the second end of the second switch is grounded;

[0039] The first end of the second capacitor is connected to the second end of the first switch, and the second end of the second capacitor is connected to the first end of the third switch;

[0040] A first end of the fourth switch is connected to a first end of the third switch, and a second end of the fourth switch is grounded;

[0041] The second end of the third switch is connected to the first end of the third capacitor and the voltage selection component respectively, and the second end of the third capacitor is grounded.

[0042] In this embodiment, the positive preset voltage is converted into the negative preset voltage by controlling the switches of the charge pump assembly.

[0043] In a second aspect, the present application provides a pin detection method for a circuit board of a display device, which is applied to a pin detection device, wherein the circuit board includes a plurality of pins to be tested;

[0044] The method comprises:

[0045] Converting the input voltage of the external power supply to a positive preset voltage;

[0046] Performing voltage conversion on the positive preset voltage to obtain a negative preset voltage;

[0047] Selecting a target pin among the plurality of pins to be tested;

[0048] The target pin is tested by the positive preset voltage and the negative preset voltage respectively to obtain a test result.

[0049] In this embodiment, the input voltage of the external power supply is converted into a positive preset voltage, and then the positive preset voltage is converted to obtain a negative preset voltage, a target pin is selected from multiple pins to be tested, and the target pin is tested by the positive preset voltage and the negative preset voltage to obtain a test result. The present application tests the positive voltage and the negative voltage of the pin to be tested, and the test method is relatively simple, and the accuracy of the detection quality of the pin to be tested is improved.

[0050] In a third aspect, the present application provides a computer-readable storage medium having computer-executable instructions stored thereon. When the computer-executable instructions are executed by a processor, the method described in the second aspect is implemented.

[0051] The computer-readable storage medium provided in the embodiment of the present application can execute the technical solution in the above method embodiment, and its beneficial effects are similar, which will not be repeated here.

[0052] In a fourth aspect, the present application provides a computer program product, including a computer program, which implements the method described in the second aspect when executed by a processor.

[0053] The computer program product provided in the embodiment of the present application can execute the technical solution in the above method embodiment, and its beneficial effects are similar, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the implementation methods in the embodiments of the present application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technology descriptions. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0055] Figure 1 A schematic diagram of a protection diode for a pin of an example of this application;

[0056] Figure 2 A schematic structural diagram of a pin detection device for a circuit board of a display device provided in an embodiment of the present application;

[0057] Figure 3 A schematic structural diagram of another pin detection device for a circuit board of a display device provided in an embodiment of the present application;

[0058] Figure 4 A schematic diagram of the connection structure between each pin to be tested and the control circuit 101 of the present application example;

[0059] Figure 5 A schematic diagram of the connection structure between each matching resistor and the multi-channel switch component 105 of the present application example;

[0060] Figure 6 The circuit diagram of the entire measurement link when measuring the target pin;

[0061] Figure 7 A schematic diagram of the structure of a charge pump assembly 03 provided in an embodiment of the present application;

[0062] Figure 8 A schematic diagram of a target pin in an example of this application having a continuous weld;

[0063] Fig. 9 This is a schematic diagram of the communication between the controller 13 and the host computer according to the example of this application;

[0064] Fig.10 is a schematic diagram of the connection between multiple analog-to-digital conversion components 12 and a controller 13;

[0065] Fig.11 A schematic flow chart of a method for detecting pins of a circuit board of a display device provided in the present application. DETAILED DESCRIPTION

[0066] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0067] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0068] In addition, the terms "include" and "have" and any variations thereof are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to those components expressly listed but may include other components not expressly listed or inherent to such products or devices.

[0069] There are currently two mainstream detection methods for TV circuit boards (such as motherboards, logic boards, etc.) screen interface detection:

[0070] Method 1

[0071] Usually, an external display device and corresponding image and audio acquisition equipment can be connected to judge the output image of the circuit board to be tested, so as to determine the welding quality of the circuit board's signal input link, signal processing module and signal output link.

[0072] Method 2

[0073] For the output link part of the circuit board, the welding quality of the output link is determined by detecting the open circuit and short circuit of the interface.

[0074] In the above method, it is necessary to configure relatively expensive equipment resources, resulting in high detection costs. At the same time, the circuit board design is required to strictly comply with the established equipment resources. The above test method process is relatively complicated, and the detection quality accuracy of welding quality is low.

[0075] Therefore, the present application provides a pin detection device for a circuit board of a display device, which is connected to an external power supply through a voltage conversion component to realize power supply for the pin detection device, and then realizes positive and negative voltage output through a charge pump component to realize positive and negative voltage testing of the pin to be tested. The testing method of the present application is relatively simple, and improves the accuracy of the detection quality of the pin to be tested, while reducing the detection cost.

[0076] Exemplarily, the pin detection device of the present application can be applied to a circuit board of a display device, which may be a television. Specifically, the pin detection device of the present application can detect the pins of the circuit board corresponding to the screen-end interface of the television. The screen-end interface may be, for example, a motherboard connector, an interface for connecting the television motherboard to the display panel, which interface corresponds to multiple pins. That is to say, the detection of the screen-end interface by the pin detection device can be understood as the detection of multiple pins corresponding to the screen-end interface.

[0077] During the circuit board development process, if there is a problem with the pin welding, it will cause the pin to be open or short-circuited, so the present application can test the open circuit and / or short circuit of the pin to determine whether there is a problem with the welding quality of the pin.

[0078] Moreover, in the circuit board, in order to improve the antistatic ability of the integrated circuit, such as Figure 1 As shown, Figure 1 This is a schematic diagram of the protection diode of the pin of the example in this application. When designing the circuit, protection diodes to the ground and the power supply are usually added to each pin. The open circuit and short circuit test is to determine whether the pin is open or short-circuited by testing the conduction voltage of the protection diode of the tested pin. For example, if the conduction voltage of the protection diode to the ground of the tested pin is greater than the preset threshold, it can be determined that the pin is open, and thus it can be determined that there is a problem with the welding quality of the pin.

[0079] It should be noted that during the test process, the circuit board to be tested needs to be tested with power off. Therefore, for each pin to be tested, the protection diode to ground and the protection diode to power supply of the pin to be tested can be connected through a short-circuit wire, and then the pin can be tested.

[0080] The technical solution of the present application is described in detail below in conjunction with specific embodiments. The following specific embodiments can be combined with each other or exist independently. The same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0081] Figure 2 A schematic diagram of a pin detection device for a circuit board of a display device provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, the pin detection device 10 includes: a control circuit 101 , a voltage conversion component 102 , a charge pump component 103 , a voltage selection component 104 and a multi-channel switch component 105 .

[0082] Among them, the voltage conversion component 102 is respectively connected to the external power supply, the charge pump component 103 and the voltage selection component 104. Specifically, the input end of the voltage conversion component 102 is connected to the external power supply, and the output end of the voltage conversion component 102 is respectively connected to the charge pump component 103 and the voltage selection component 104.

[0083] The voltage selection component 104 is connected to the multi-channel switch component 105, the multi-channel switch component 105 is connected to the control circuit 101, and the control circuit 101 is connected to multiple pins to be tested of the circuit board to be tested. Exemplarily, the control circuit 101 is connected to multiple pins to be tested on the circuit board to be tested where the screen end interface to be tested is located.

[0084] The control circuit 101 is configured to test a plurality of pins to be tested of the circuit board to be tested, specifically, to test whether the plurality of pins to be tested are open-circuited or short-circuited, so as to determine whether there is a problem with the welding quality of the pins to be tested.

[0085] The voltage conversion component 102 is configured to convert the input voltage of the external power supply into a positive preset voltage. For example, the input voltage is 12V (volts), and the positive preset voltage can be +3.3V. For example, the voltage conversion component 102 can be a DCDC converter, that is, a direct current-to-direct current converter, and the DCDC converter can generate a 3.3V operating voltage based on 12V.

[0086] The charge pump component 103 is configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage. Taking the positive preset voltage as an example, the charge pump component 103 can perform voltage conversion on +3.3V to output -3.3V.

[0087] The voltage selection component 104 is configured to sequentially select the positive preset voltage and the negative preset voltage, or sequentially select the negative preset voltage and the positive preset voltage. Specifically, the voltage selection component 104 can obtain a control signal, which is used to indicate that when a certain pin to be tested is detected, the positive preset voltage and the negative preset voltage are sequentially selected, or the negative preset voltage and the positive preset voltage are sequentially selected, that is, the positive and negative voltage detection order of the pin to be tested, so that the voltage selection component 104 can be controlled according to the control signal so that the pin to be tested is connected to the positive preset voltage or the negative preset voltage. Exemplarily, the control signal can be sent by the control circuit 101.

[0088] The multi-channel switch component 105 is configured to select a target pin among a plurality of pins to be tested.

[0089] The control circuit 101 is specifically configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain the test result. Specifically, the test result includes the test result of the positive preset voltage and the test result of the negative preset voltage.

[0090] In this embodiment, the pin detection device 10 includes a control circuit 101, a voltage conversion component 102, a charge pump component 103, a voltage selection component 104 and a multi-channel switch component 105. The control circuit 101 is connected to multiple pins to be tested of the circuit board to be tested, the voltage conversion component 102 is connected to an external power supply, the charge pump component 103 is connected to the voltage conversion component 102, the voltage selection component 104 is respectively connected to the charge pump component 103, the voltage conversion component 102 and the multi-channel switch component 105, and the multi-channel switch component 105 is connected to the control circuit 101. Among them, the control circuit 101 is configured to test multiple pins to be tested, the voltage conversion component 102 is configured to convert the input voltage of the external power supply into a positive preset voltage, the charge pump component 103 is configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage, the voltage selection component 104 is configured to sequentially select the positive preset voltage and the negative preset voltage, the multi-channel switch component 105 is configured to select the target pin among the multiple pins to be tested, and the control circuit 101 is specifically configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain the test result. The present application realizes the testing of positive voltage and negative voltage on the pin to be tested by the charge pump, the testing method is relatively simple, and the accuracy of the detection quality of the pin to be tested is improved.

[0091] Figure 3 A schematic diagram of the structure of another pin detection device for a circuit board of a display device provided in an embodiment of the present application, such as Figure 3As shown, the pin detection device 10 includes: a control circuit 101 , a voltage conversion component 102 , a charge pump component 103 , a voltage selection component 104 and a multi-channel switch component 105 .

[0092] The connection relationship and description between the control circuit 101, the voltage conversion component 102, the charge pump component 103, the voltage selection component 104 and the multi-channel switch component 105 refer to the above embodiments and will not be repeated here.

[0093] The control circuit 101 includes a plurality of matching resistors 11 , a plurality of analog-to-digital conversion components 12 and a controller 13 .

[0094] The plurality of matching resistors 11 are respectively connected to the plurality of pins to be tested through the plurality of first connecting wires, the plurality of analog-to-digital conversion components 12 are connected to the plurality of first connecting wires, and the controller is connected to the plurality of analog-to-digital conversion components.

[0095] In a possible implementation, the analog-to-digital conversion component 12 may be an analog-to-digital converter with multiple input terminals. For example, the analog-to-digital conversion component 12 may be an analog-to-digital converter with six input terminals, each of which may be connected to a first connecting line. Then, if the number of pins to be tested is 12, two analog-to-digital conversion components are required, that is, six pins to be tested are connected to one analog-to-digital conversion component. Figure 3 Only the connection between two pins to be tested and the control circuit 101 is shown.

[0096] It can be understood that the number of analog-to-digital conversion components 12 can be determined based on the number of interfaces to be tested and the number of input terminals of the analog-to-digital conversion component 12. This application does not limit the number of input terminals of the analog-to-digital conversion component 12 and the number of mode conversion components 12.

[0097] In one possible implementation, for any pin to be tested, the pin to be tested is connected to a first diode and a second diode, the first diode is connected to a power supply, and the second diode is grounded. When the voltage selection component 104 selects the positive preset voltage, the control circuit 101 is configured to: determine the first conduction voltage of the first diode to determine whether the pin to be tested is short-circuited or open-circuited based on the first conduction voltage.

[0098] If the voltage selection component 104 selects the negative preset voltage, the control circuit 101 is configured to measure and determine the second conduction voltage of the second diode to determine whether the pin to be tested is short-circuited or open-circuited according to the second conduction voltage.

[0099] For example, taking the two analog-to-digital conversion components in the above example as an example, refer to Figure 4 ,pass Figure 4 The connection structure between each pin to be tested and the control circuit 101 is shown, and Figure 4Only the structures of the protection diodes of the pins Pin1 and Pin12 to be tested (i.e., the first diode and the second diode) are shown, and the other pins to be tested are similar. Figure 4 TP in the figure represents a voltage measurement point, and the matching resistor in the figure is connected to the multi-channel switch component 105. In order to clearly show the connection between each matching resistor and the multi-channel switch component 105, Figure 4 For example, through Figure 5 105. In order to clearly show the connection between the matching resistors and the multi-channel switch component 105, Figure 5 The connection relationship between the pin to be tested and the analog-to-digital conversion component 12 and the connection between the analog-to-digital conversion component 12 and the controller 13 are not shown.

[0100] For any analog-to-digital conversion component 12 , it is configured to measure the voltage value of the pin to be tested connected to the analog-to-digital conversion component 12 , that is, to measure the voltage value of the voltage measurement point TP.

[0101] The controller 13 is configured to obtain voltage values ​​sent by the multiple analog-to-digital conversion components 12, and determine whether the multiple pins to be tested are short-circuited or open-circuited according to the voltage values ​​sent by the multiple analog-to-digital conversion components 12.

[0102] In one possible implementation, Figure 5 As shown, the voltage selection component 104 may be a binary switch configured to select a positive preset voltage or a negative preset voltage.

[0103] Exemplarily, the target pin is TP1, and the voltage selection component 104 selects the positive preset voltage, then the controller 13 can obtain the voltage value sent by the analog-to-digital conversion component corresponding to the target pin, and the voltage value is the voltage value of the target pin when the positive preset voltage is connected, that is, the voltage value can also be understood as the conduction voltage of the first diode of the target pin. The controller 13 can compare the voltage value with the preset threshold to determine whether the target pin is short-circuited or open-circuited, wherein the preset threshold may include a first preset threshold and a second preset threshold, the first preset threshold is used to determine whether it is open-circuited, and the second preset threshold is used to determine whether it is short-circuited. For example, the first preset threshold is 0.7V. If the voltage value is greater than 0.7V, it is determined that the target pin is open-circuited when the positive preset voltage is connected.

[0104] As for the size of the matching resistor connected to each of the above-mentioned pins to be tested, it can be determined, for example, in the following manner:

[0105] Figure 6 When measuring the target pin, the circuit diagram of the entire measurement link is shown. The resistance of the entire test link is obtained by the following formula (1):

[0106] R=R104 +R 105 +R1+R2 (1)

[0107] Among them, R 104 The resistance of the voltage selection component 104, R 105 is the resistance of the multi-channel switch component 105, R 104 and R 105 It is known that the specific information can be found in the chip manual. R1 is the resistance value of the matching resistor. ， R2 is the on-resistance of the diode, and the resistance value of R2 can be ignored. When the output current I is set, R1 can be obtained by the following formula (2):

[0108]

[0109] Wherein, U is a preset voltage, such as 3.3V, and I is an output current.

[0110] The matching resistor can limit the output current of the charge pump to ensure that the current is within the specifications of the circuit board to be tested, thereby preventing the test from causing damage to the circuit board to be tested.

[0111] Next, the specific structure of the charge pump assembly 103 is described:

[0112] Figure 7 A schematic diagram of the structure of a charge pump assembly 03 provided in an embodiment of the present application is shown in FIG. Figure 7 As shown, the charge pump component 103 includes a first capacitor, a second capacitor, a third capacitor, a first switch, a second switch, a third switch and a fourth switch.

[0113] The first end of the first capacitor is connected to the first end of the first switch, the first end of the first switch is connected to the voltage conversion component 102, and the second end of the first capacitor is grounded.

[0114] The first end of the second switch is connected to the second end of the first switch, and the second end of the second switch is grounded.

[0115] The first end of the second capacitor is connected to the second end of the first switch, and the second end of the second capacitor is connected to the first end of the third switch.

[0116] A first end of the fourth switch is connected to the first end of the third switch, and a second end of the fourth switch is grounded.

[0117] The second end of the third switch is connected to the first end of the third capacitor and the voltage selection component respectively, and the second end of the third capacitor is grounded.

[0118] exist Figure 7In the figure, 1 and 2 represent the first end and the second end respectively. For example, 1 of the first switch represents the first end, 2 of the first switch represents the second end, 1 of the first capacitor represents the first end, and 2 of the first capacitor represents the second end.

[0119] like Figure 7 As shown, when the first switch and the fourth switch are closed, and the second switch and the third switch are opened, the input voltage VIN (positive preset voltage) charges the second capacitor to VIN. When the first switch and the fourth switch are opened, and the second switch and the third switch are closed, the left end of the second capacitor is grounded, and the right end is connected to the output VOUT. At this time, because the charge on the two plates of the second capacitor cannot be reduced suddenly, the voltage at the left end slowly decreases to 0, and a voltage section becomes a negative voltage until -VIN (negative preset voltage), and so on.

[0120] The third capacitor is a filter capacitor. In order to reduce the voltage ripple of the detection circuit, the capacitance value of the third capacitor can be controlled to reduce the voltage ripple.

[0121] Exemplarily, the capacitance value of the third capacitor can be determined by formula (3):

[0122]

[0123] Wherein, R is the sum of the matching resistance and the input impedance of the circuit board being tested, A is a preset parameter, and the value range may be [3, 5], and T is the switching period between the positive preset voltage and the negative preset voltage.

[0124] During the circuit board development process, due to reasons such as welding process, it is possible that the pins may be soldered together.

[0125] Since the analog-to-digital conversion component of the present application can be connected to multiple pins to be tested, when testing the target pin, if the target pin is continuously welded, the nearby pins to be tested that are continuously welded to the target pin will also be energized as the target pin is energized. It can be determined whether the target pin is continuously welded based on the analog-to-digital conversion component corresponding to the target pin.

[0126] Specific:

[0127] When testing the target pin and obtaining the voltage value corresponding to the target pin, the voltage values ​​of multiple second pins near the target pin can be obtained based on the analog-to-digital conversion component corresponding to the target pin, and then it can be determined whether there is a continuous weld on the target pin based on the voltage values ​​of the multiple second pins.

[0128] Specifically, if there is a first voltage value among the voltage values ​​of the plurality of second pins that is the same as the voltage value of the target pin, it is determined that the target pin is connected to the second pin corresponding to the first voltage value by welding.

[0129] In a possible implementation, since the pins to be tested that are welded to the target pins are generally pins near the target pins, the target pins and these nearby pins to be tested are usually connected to an analog-to-digital conversion component, so the analog-to-digital conversion component corresponding to the target pin and the analog-to-digital conversion component corresponding to the second pin are the same analog-to-digital conversion component, so that when obtaining the voltage of the target pin, the voltage value of the second pin that may be welded to the target pin can be obtained through the analog-to-digital conversion component corresponding to the target pin. Therefore, the multiple second pins may include pins near the target pin connected to an analog-to-digital conversion component. Exemplarily, the multiple second pins may also be two pins before and after the target pin, or four pins before and after the target pin, etc.

[0130] In another possible implementation, if there is a large-scale continuous welding situation, the multiple second pins include not only pins nearby the target pin connected to an analog-to-digital conversion component, but also pins to be tested connected on multiple analog-to-digital conversion components near the analog-to-digital conversion component corresponding to the target pin, so as to avoid failure to detect when there is a large-scale continuous welding situation.

[0131] For example, Figure 8 As shown, Figure 8 The following is a schematic diagram of the situation where the target pin is continuously welded. When testing the target pin Pin2, the voltage values ​​of Pin1 and Pin3 are obtained respectively to determine whether Pin2 is continuously welded with Pin1 and Pin3. Figure 8 As shown, Pin2 and Pin3 are continuously welded, so the voltage value of Pin3 is the same as the voltage value of Pin2.

[0132] Next, the communication between the various components in the pin detection device 10 is described:

[0133] In a possible implementation, when the multi-channel switch component 105 selects a target pin among multiple pins to be tested, the multi-channel switch component 105 can obtain a test instruction, which is used to instruct to select the target pin among multiple pins to be tested, and then select the target pin according to the test instruction.

[0134] Specifically, the test instruction can be sent by the controller 13 to the multi-channel switch component 105. When the controller 13 completes the test of the current pin, that is, completes the test of the positive preset voltage and the negative preset voltage of the pin, it can instruct the multi-channel switch component 105 to select the target pin to be tested through the test instruction.

[0135] In one possible implementation, Fig. 9As shown, the controller 13 can communicate with the host computer, and the controller 13 can receive control instructions from the host computer to generate the above-mentioned test instructions, which can include the test sequence of the pins to be tested, the switching cycle of the positive preset voltage and negative preset voltage test of each pin to be tested, etc.

[0136] As for the voltage selection component 104 switching the positive preset voltage and the negative preset voltage, illustratively, the voltage selection component 104 can select to conduct the positive preset voltage or the negative preset voltage according to the received switching instruction, for example, after the positive preset voltage is conducted, and after the controller 13 completes the acquisition of the conduction voltage of the first diode of a certain pin to be tested and the conduction voltage is sent to the host computer, the voltage selection component 104 can receive the switching instruction to control the voltage selection component 104 to conduct the negative preset voltage. The host computer can also generate a test report according to the test results of each pin to be tested.

[0137] For the communication between the multiple analog-to-digital conversion components 12 and the controller 13, Fig.10 is a schematic diagram of the connection between multiple analog-to-digital conversion components 12 and the controller 13, such as Fig.10 As shown, taking two analog-to-digital conversion components 12 as an example, each analog-to-digital conversion component is connected to the controller 13 via two connecting lines, wherein CS1 and CS2 are chip select signal lines, and the controller 13 can set the levels of CS1 and CS2 to select the analog-to-digital conversion component for communication. For example, the controller 13 sets CS1 to a low level, and the controller 13 can communicate with the analog-to-digital conversion component corresponding to CS1 via the second connecting line. Exemplarily, the second connecting line can be a signal line for transmitting a clock signal, or a data output signal line (Master Out Slave In, MOSI), or a data input signal line (Master In Slave Out, MISO), that is, the signal line for transmitting a clock signal, MOSI, and MISO can share the second connecting line.

[0138] That is, the controller 13 can set CS1 to a low level, and then output a clock through the second connection line, and then output and receive data on the second connection line.

[0139] In the embodiment of the present application, the controller 13 may be a microcontroller unit (MCU), and in the circuit diagram of the above embodiment, GND represents grounding, and VDD represents power supply.

[0140] Fig.11 The present application provides a flow chart of a method for detecting pins of a circuit board of a display device. The method can be applied to the above-mentioned pin detection device 10. The circuit board includes a plurality of pins to be tested, such as Fig.11As shown, the method comprises the following steps:

[0141] S1101 , converting the input voltage of the external power supply into a positive preset voltage.

[0142] S1102 , performing voltage conversion on the positive preset voltage to obtain a negative preset voltage.

[0143] S1103 . According to the control signal, sequentially select the positive preset voltage and the negative preset voltage, or sequentially select the negative preset voltage and the positive preset voltage.

[0144] S1104 , select a target pin among multiple pins to be tested.

[0145] S1105 , testing the target pin by using a positive preset voltage and a negative preset voltage respectively, and obtaining a test result.

[0146] For the specific implementation of the above steps, please refer to the above embodiments, which will not be described again here.

[0147] In this embodiment, the input voltage of the external power supply is converted into a positive preset voltage, and then the positive preset voltage is converted to obtain a negative preset voltage, a target pin is selected from multiple pins to be tested, and the target pin is tested by the positive preset voltage and the negative preset voltage to obtain a test result. The present application tests the positive voltage and the negative voltage of the pin to be tested, and the test method is relatively simple, and the accuracy of the detection quality of the pin to be tested is improved.

[0148] The present application also provides a computer-readable storage medium, which may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes. Specifically, the computer-readable storage medium stores computer execution instructions, and the computer execution instructions are used for the methods in the above embodiments. The specific implementation methods and technical effects are similar and will not be repeated here.

[0149] The present application also provides a program product, which includes a computer program stored in a readable storage medium. When the computer program is executed by a computer, the technical solution shown in the above method embodiment is executed. The specific implementation method and technical effect are similar and will not be repeated here.

[0150] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0151] For ease of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are intended to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

[0152] In this application, "multiple" means two or more. The first, second, etc. descriptions that appear in the embodiments of this application are only used for illustration and distinction of the described objects. There is no order, nor does it represent a special limitation on the number of devices in the embodiments of this application, and cannot constitute any limitation on the embodiments of this application. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and do not represent the difference in size, priority, or importance of the two thresholds.

[0153] In this application, "exemplary", "in some embodiments", "in other embodiments", etc. are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present concepts in a concrete way.

[0154] In this application, "of", "corresponding, relevant", "corresponding", and "associated" can sometimes be used interchangeably. It should be noted that when the distinction is not emphasized, the meanings they express are consistent. In the embodiments of this application, communication and transmission can sometimes be used interchangeably. It should be noted that when the distinction is not emphasized, the meanings they express are consistent. For example, transmission can include sending and / or receiving, which can be a noun or a verb.

Claims

1. A pin detection device for a circuit board of a display device, characterized in that: The pin detection device comprises: A control circuit is connected to a plurality of pins to be tested of a circuit board to be tested and is configured to test the plurality of pins to be tested; A voltage conversion component, connected to an external power source, and configured to convert an input voltage of the external power source into a positive preset voltage; a charge pump component connected to the voltage conversion component and configured to perform voltage conversion on the positive preset voltage to output a negative preset voltage; A voltage selection component, connected to the charge pump component and the voltage conversion component respectively, and configured to sequentially select the positive preset voltage and the negative preset voltage, or sequentially select the negative preset voltage and the positive preset voltage; a multi-channel switch component, connected to the control circuit and the voltage selection component respectively, and configured to select a target pin among the plurality of pins to be tested; The control circuit is specifically configured to test the target pin through the positive preset voltage and the negative preset voltage respectively to obtain a test result.

2. The pin detection device according to claim 1, characterized in that: The control circuit comprises: A plurality of matching resistors are respectively connected to the plurality of pins to be tested through a plurality of first connecting wires; A plurality of analog-to-digital conversion components connected to the plurality of first connecting lines, for any one of the analog-to-digital conversion components, is configured to measure a voltage value of a pin to be tested connected to the analog-to-digital conversion component; The controller is connected to the multiple analog-to-digital conversion components and is configured to obtain voltage values ​​sent by the multiple analog-to-digital conversion components and determine whether the multiple pins to be tested are short-circuited or open-circuited based on the voltage values ​​sent by the multiple analog-to-digital conversion components.

3. The pin detection device according to claim 2, characterized in that: The controller is configured to: Acquire voltage values ​​of a plurality of second pins near the target pin; It is determined whether the target pin has a continuous weld according to the voltage values ​​of the plurality of second pins.

4. The pin detection device according to claim 3, characterized in that: The analog-to-digital conversion component corresponding to the target pin and the analog-to-digital conversion component corresponding to the second pin are the same analog-to-digital conversion component.

5. The pin detection device according to claim 3 or 4, characterized in that: The controller is configured to: If, among the voltage values ​​of the plurality of second pins, there is a first voltage value that is the same as the voltage value of the target pin, it is determined that the target pin is soldered to the second pin corresponding to the first voltage value.

6. The pin detection device according to any one of claims 1 to 5, characterized in that: For any pin to be tested, the pin to be tested is connected to a first diode and a second diode, the first diode is connected to a power supply, and the second diode is grounded; When the voltage selection component selects the positive preset voltage, the control circuit is configured to: measure a first conduction voltage of the first diode to determine whether the pin to be tested is short-circuited or open-circuited according to the first conduction voltage; If the voltage selection component selects the negative preset voltage, the control circuit is configured to measure a second conduction voltage of the second diode to determine whether the pin to be tested is short-circuited or open-circuited according to the second conduction voltage.

7. The pin detection device according to claim 1, characterized in that: The multi-channel switch component is configured as follows: Acquire a test instruction, wherein the test instruction is used to instruct to select the target pin among the plurality of pins to be tested; According to the test instruction, the target pin is enabled.

8. The pin detection device according to claim 1, characterized in that: The charge pump component includes a first capacitor, a second capacitor, a third capacitor, a first switch, a second switch, a third switch and a fourth switch; The first end of the first capacitor is connected to the first end of the first switch, the first end of the first switch is connected to the voltage conversion component, and the second end of the first capacitor is grounded; The first end of the second switch is connected to the second end of the first switch, and the second end of the second switch is grounded; The first end of the second capacitor is connected to the second end of the first switch, and the second end of the second capacitor is connected to the first end of the third switch; A first end of the fourth switch is connected to a first end of the third switch, and a second end of the fourth switch is grounded; The second end of the third switch is connected to the first end of the third capacitor and the voltage selection component respectively, and the second end of the third capacitor is grounded.

9. A method for detecting pins of a circuit board of a display device, characterized in that: Applicable to a pin detection device; the circuit board includes a plurality of pins to be tested; The method comprises: Converting the input voltage of the external power supply to a positive preset voltage; Performing voltage conversion on the positive preset voltage to obtain a negative preset voltage; According to a control signal, the positive preset voltage and the negative preset voltage are sequentially switched on, or the negative preset voltage and the positive preset voltage are sequentially switched on; Selecting a target pin among the plurality of pins to be tested; The target pin is tested by the positive preset voltage and the negative preset voltage respectively to obtain a test result.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, the method of claim 9 is implemented.

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