Large-scale automatic contact resistance testing machine

Abstract

The utility model relates to a large-scale automatic contact resistance testing machine which comprises a shell, a machine frame, a control panel, a positioning device, a warning device, a moving device, a heat dissipation device and a man-machine interaction device. The testing machine can automatically and quickly test the contact resistance value of the socket, realizes batch testing and quick screening, improves the testing efficiency, and reduces the testing error caused by manpower; the test machine provides 1024 test channels, meets the test requirements of most sockets, has universality and can be repeatedly used, a user only needs to replace a test substrate according to different test sockets, and part of the test channels of the machine can be flexibly gated for small-package sockets; the measurable contact resistance range of the testing machine is 0-800 milliohms, and the contact resistance values of most socket pins are covered; the testing machine provides three measuring circuits with different gears for each testing channel, and the measuring gears are automatically switched according to the actually measured resistance value of the contact resistor so as to improve the measuring precision.

Description

Technical Field

[0001] The utility model relates to a large-scale automatic contact resistance testing machine, belonging to the technical field of semiconductor testing. Background Art

[0002] The contact resistance between the test socket and the LGA packaged CPU chip base is an important key parameter that determines the performance of the connector product. It is an important test link for product assembly submission and factory inspection, and requires 100% testing. During the high-temperature aging test, low-temperature aging test, and strongly accelerated steady-state damp heat test, when the chip test yield rate decreases, it is necessary to promptly rule out whether the test yield rate decreases due to excessive contact resistance of the test socket on the board. Excessive pin contact resistance leads to problems such as decreased circuit efficiency, increased heat generation, and signal transmission loss. In particular, the increase in contact resistance of pins that transmit large current signals will cause an abnormal increase in heat at the contact point, resulting in chip melting and even burning of the socket pin board.

[0003] At present, the test of contact resistance in China is mainly carried out manually with a microresistance meter. Since these test instruments are all manually testing the contact resistance by using the meter pen of the meter to touch the two ends of the contact resistance of the connector, only one channel can be tested at a time, and the test efficiency is low. They are only suitable for product research and trial production testing, but not suitable for batch testing of sockets and rapid measurement of contact resistance in various test processes. Moreover, long-term testing will cause fatigue to the operator and affect the measurement quality.

[0004] Therefore, it is necessary to invent a large-scale automated contact resistance testing machine to solve the above problems by replacing manual testing with automatic measurement and recording testing equipment. Summary of the invention

[0005] The purpose of the utility model is to provide a large-scale automated contact resistance testing machine, which can automatically and quickly test the contact resistance value of a socket, realize batch testing and rapid screening, improve test efficiency, and reduce test errors caused by manual labor.

[0006] In order to achieve the above object, the utility model provides the following technical solutions:

[0007] A large-scale automated contact resistance testing machine, comprising:

[0008] shell;

[0009] Machine frame: the machine frame is arranged in the shell;

[0010] Control board; the control board includes a high-precision constant current source, a test probe, a voltage detection circuit, and a control circuit. The high-precision constant current source is transmitted to the test channel of the substrate through the test probe to provide a constant current source for the contact resistance value of each chain, thereby converting the contact resistance of each chain into a voltage signal;

[0011] Positioning device; the positioning device is arranged on the machine frame, the positioning device comprises four positioning pins adapted to the substrate, the positioning pins are provided with a position sensor, and the position sensor is electrically connected to the control board;

[0012] A warning device; the warning device comprises a red indicator light, a green indicator light, and an orange indicator light arranged on the housing, and the warning device is electrically connected to the control panel;

[0013] Motion device; the motion device includes a load-bearing tray, a motion plane, a positioning axis, a motion axis, a power source and a distance measuring sensor. The load-bearing tray is fixed below the control panel, and the motion plane is fixed below the load-bearing tray. A plurality of distance measuring sensors are installed below the motion plane. The positioning axis and the motion axis are perpendicular to the motion plane to respectively realize the positioning and motion functions. The power source provides the motion axis with clockwise and counterclockwise rotation power, thereby driving the motion plane to move up and down. During the upward movement of the motion plane, the distance measuring sensor collects the moving distance of the motion plane in real time by detecting the distance between the motion plane and the bottom of the test machine, and transmits the collected moving distance data to the control panel; when the moving distance value is less than 64cm, the control panel controls the motion plane to continue to move up, otherwise it stops moving;

[0014] Heat dissipation device; the heat dissipation device is arranged below the moving plane, and the control board collects the temperature on the board and the temperature inside the machine frame. When the collected temperature is greater than 40°C, the control board starts the heat dissipation device, otherwise it turns off the heat dissipation device, thereby reducing the measurement error caused by the change of resistance value caused by heat;

[0015] Human-computer interaction device; the human-computer interaction device is arranged on the housing, the human-computer interaction device is electrically connected to the control panel, and is used to display, store, print, and analyze the contact resistance test results. The user can also manually control the test process or view the test results. The human-computer interaction device includes a human-computer interaction interface, a mouse, and a keyboard;

[0016] Among them, the control board collects the state of the position sensor to detect the installation state of the substrate. When the detection state is that the installation is correct, the control board lights up the orange indicator light, sends an upward movement signal to start the movement device to move upward, and the test probe is connected to the substrate test channel. Each group of test channels has a status detection pin connected to the test probe. The control board detects the level change of the status pin of each group of test channels. When the status pin level is 3.3±0.3V, the control board provides a constant current source for the group of test channels. When the status pin level is not 3.3±0.3V, the group of tests is not powered and the alarm information is transmitted to the human-computer interaction interface display; when the detection state is not that the installation is correct, the red indicator light is lit and the alarm information is transmitted to the human-computer interaction interface display, and the movement device is not started; the control board provides a constant current to the substrate through the detection test probe, and transmits the voltage across the contact resistance of each chain on the substrate to the voltage detection circuit.

[0017] Preferably, the distance measuring sensor is a laser distance measuring sensor.

[0018] Preferably, the positioning shaft is a smooth rod, and the moving shaft is a worm rod.

[0019] Preferably, the power source is an electric motor.

[0020] Preferably, the heat dissipation device is a heat sink.

[0021] Preferably, the high-precision constant current source is a 1024-channel high-precision constant current source, and the voltage detection circuit is a 1024-channel voltage detection circuit.

[0022] The beneficial effects of the utility model are:

[0023] The utility model provides a large-scale automated contact resistance test machine, which can automatically and quickly test the contact resistance value of a socket, realize batch testing and rapid screening, improve test efficiency, and reduce test errors caused by manual labor; the test machine provides 1024 test channels to meet most socket test requirements, has universality and can be reused, and according to different test sockets, the user only needs to replace the test substrate, and for small-package sockets, some test channels of the machine can be flexibly selected; the contact resistance range that the test machine can measure is 0-800 milliohms, covering most socket pin contact resistance values; the test machine provides 3 different gear measurement circuits for each test channel, and automatically switches the measurement gear according to the actual measured contact resistance value to improve the measurement accuracy.

[0024] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the overall structure of a large-scale automated contact resistance test machine provided by the utility model;

[0027] Figure 2 The utility model provides a schematic diagram of the internal structure of a large-scale automated contact resistance testing machine.

[0028] In the accompanying drawings, the reference numerals of the various components are as follows:

[0029] 1. Test substrate; 11. Positioning hole; 12. Fixing hole; 13. Fixing bracket; 2. Dummy piece; 3. Control board; 31. Test probe; 4. Positioning pin; 5. Warning device; 61. Load-bearing tray; 62. Moving plane; 63. Positioning axis; 64. Moving axis; 65. Power source; 66. Distance measuring sensor; 7. Heat dissipation device; 81. Human-computer interaction interface; 82. Mouse; 83. Keyboard; 9. Casing. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] See also Figure 1 to Figure 2 The large-scale automated contact resistance testing machine shown in one embodiment of the utility model can automatically and quickly test the contact resistance value of the socket, realize batch testing and rapid screening, improve test efficiency, and reduce test errors caused by manual labor.

[0034] This embodiment uses a dummy chip 2, a socket to be tested, a test substrate 1 and a test machine to simulate the contact resistance test in the actual production process, and the test principle adopts the Kelvin four-wire method.

[0035] Dummy chip 2 is a special chip customized for measuring socket pins and the contact resistance between pins and chips. The chip connects different pins in series to form a chain according to specific constraints. The chip can be divided into N chains, and the number of pins in each chain is an even number. The size, material, and appearance of dummy chip 2 are consistent with the actual chip to be tested, and can be used to simulate the contact resistance between the real chip and the test socket pins.

[0036] The test substrate 1 includes a socket installation area to be tested, a test channel area (for connecting to a test machine), a voltage measurement circuit across the contact resistance, a positioning hole 11, a fixing hole 12, and a fixing bracket 13. The test substrate 1 provides 1024 contact resistance test channels, which can be divided into groups of 64 channels or 128 channels. Each chain corresponds to 1 test channel, and each test channel has an independent voltage measurement circuit across the contact resistance. The positioning hole 11 is connected to the positioning pin 4 of the positioning device to determine the installation status of the substrate. The fixing bracket 13 is installed on the substrate to increase the strength and toughness of the substrate, which facilitates the connection between the machine test probe 31 and the test channel on the board. The substrate equipped with the fixing bracket 13 is fixed to the test machine through fasteners and fixing holes 12.

[0037] The socket base and the spring pin plate of the socket to be tested together form a slot for placing the dummy chip 2. The socket base is connected and fastened to the socket cover through hinges, buckles, and buckle slots. The hinge allows the socket cover to be flipped 100 degrees relative to the socket base. The spring pin plate is fixed to the bottom of the base by 4 fixing screws. The spring pins of the spring pin plate correspond one-to-one to the pins of the dummy chip 2. When the upper cover and the base are closed in place, the spring pins extend from the pin plate and connect to the test substrate 1, transferring the pins of the dummy chip 2 to the test substrate 1, thereby realizing the pin connection of the entire chain. The socket pins and the contact resistance between the pins and the chip are measured in units of chains to reduce measurement errors and the number of test channels. The above-mentioned installation relationship between the socket and the dummy chip 2 is only one of them. The installation form of the LGA packaged CPU chip base and the dummy chip 2 is similar.

[0038] The test machine comprises: a housing, a machine frame, a control panel 3, a positioning device, an alarm device 5, a motion device, a heat dissipation device 7, and a human-computer interaction device.

[0039] The control board 3 includes 1024 high-precision constant current sources, test probes 31, 1024 voltage detection circuits, and control circuits. It also collects the status of the positioning device and the alarm device 5, controls the start and stop of the motion device and the heat dissipation device 7, and transmits the test results to the human-computer interaction device for display, storage, and printing.

[0040] The high-precision constant current source is transmitted to the test channel of the substrate through the test probe 31, providing a constant current source for the contact resistance value of each chain, thereby converting the contact resistance of each chain into a voltage signal. The control board 3 provides a constant current of a specified number of channels (≤1024 channels) to the substrate through the test probe 31, and transmits the corresponding channel voltage to the voltage detection circuit of the control board 3. Each chain connects the machine constant current to the substrate through two test probes 31, thereby converting the contact resistance value of each chain into a voltage signal.

[0041] The voltage detection circuit is an amplifier circuit with three magnifications corresponding to the voltage of each chain of the substrate. The amplified voltage is converted into a digital value that can be recognized by the control circuit through three AD acquisition channels. The control circuit automatically analyzes the voltage values ​​collected by three different AD channels of the same chain. When the actual acquisition value of the first AD channel is less than 90% of the channel setting value, the contact resistance is calculated based on the voltage value collected by the first channel. Otherwise, the second channel value is read and compared, and so on until the third channel. If the actual acquisition value of the third AD channel is still greater than 90% of the channel setting value, an error is reported directly. The amplifier circuit has a high-impedance input, and the current flowing through the two ends of the test line is almost zero, ensuring that the detected voltage value is only the voltage across the contact resistance. The constant current and voltage detection lines of each test channel are separated from each other, do not interfere with each other, and form independent circuits to eliminate the influence of the test line resistance.

[0042] Specifically, the contact resistance range that can be measured by the test machine is divided into three sections: 0-100mΩ, 101-200mΩ, and 201-800mΩ. The first section 0-100mΩ is commonly used, and the other two ends are to improve the scalability of the test machine. The constant current at both ends of the contact resistance is 100mA DC, and the contact resistance range of the connector is 1mΩ~50mΩ. According to Ohm's law, the input signal voltage range of the operational amplifier is 0.1mV~5mV. In order to improve the acquisition accuracy of the AD chip, the voltage signal range after the amplifier is amplified is required to be no greater than 90% of the AD input range.

[0043] The positioning device is arranged on the machine frame, and the positioning device includes four positioning pins 4 adapted to the substrate, and the positioning pins 4 are provided with position sensors, and the position sensors are electrically connected to the control board 3. The warning device 5 includes a red indicator light, a green indicator light, and an orange indicator light arranged on the housing, and the warning device 5 is electrically connected to the control board 3.

[0044] The motion device includes a load-bearing tray 61, a motion plane 62, a positioning shaft 63, a motion shaft 64, a power source 65 and a distance sensor 66. The load-bearing tray 61 is fixed below the control board 3 to increase the strength and toughness of the control board 3 and buffer the force when the test probe 31 of the control board 3 is docked with the substrate test channel.

[0045] The moving plane 62 is fixed below the load-bearing tray 61 , and two distance measuring sensors 66 are installed below the moving plane 62 .

[0046] The positioning axis 63 and the moving axis 64 are perpendicular to the moving plane 62, realizing the positioning and moving functions respectively. The power source 65 provides the moving axis 64 with clockwise and counterclockwise rotation power, thereby driving the moving plane 62 to move up and down. During the upward movement of the moving plane 62, the distance measuring sensor 66 collects the moving distance of the moving plane 62 in real time by detecting the distance between the moving plane 62 and the bottom of the test machine, and transmits the collected moving distance data to the control board; when the moving distance value is less than 64cm (when the distance between the moving plane 62 and the bottom of the test machine is 64cm, the control board 3 is in the correct test position), the control board 3 controls the moving plane 62 to continue to move up, otherwise it stops moving.

[0047] In this embodiment, the distance measuring sensor 66 is a laser distance measuring sensor, the positioning shaft 63 is a light rod, the motion shaft 64 is a worm gear, and the power source 65 is a motor, so as to achieve precise displacement and positioning of the motion plane 62 .

[0048] The control board 3 collects the status of the position sensor to detect the installation status of the substrate. When the detection status is that the installation is correct, the control board 3 lights up the orange indicator light, sends an upward signal to start the movement device to move up, and the test probe 31 is connected to the substrate test channel. Each group of test channels has a status detection pin connected to the channel and the test probe 31, and the control board 3 detects the level change of the status pin of each group of test channels. When the status pin level is 3.3±0.3V, the control board 3 provides a constant current source for the group of test channels. When the status pin level is not 3.3±0.3V, the group of tests is not powered and the alarm information is transmitted to the human-computer interaction interface 81 for display. When the detection status is not that the installation is correct, the red indicator light is lit and the alarm information is transmitted to the human-computer interaction interface 81 for display, and the movement device is not started.

[0049] The control board 3 provides a constant current to the substrate by detecting the test probe 31, and transmits the voltage across the contact resistance of each chain on the substrate to the voltage detection circuit. The control board 3 provides a constant current to the substrate through the test probe 31, and transmits the voltage across the contact resistance of each chain to the voltage detection circuit of the control board 3. After the test is completed, the control board 3 sends a downward movement signal to the power source 65 of the motion device, the power source 65 controls the motion shaft 64 to rotate counterclockwise, the motion plane 62 moves downward, and the distance sensor 66 collects the moving distance of the motion plane 62 in real time, and transmits the collected distance data to the control board 3. After the test probe 31 is separated from the substrate test channel and descends to the set position height, the control board 3 sends a stop command to the power source 65, and then lights up the green indicator light.

[0050] The heat sink 7 is arranged below the moving plane 62. The control board 3 collects the temperature on the board and the temperature inside the machine frame. When the collected temperature is greater than 40°C, the control board 3 starts the heat sink 7, otherwise it turns off the heat sink 7, thereby reducing the measurement error caused by the change of resistance value caused by heat. Specifically, in this embodiment, the heat sink 7 is a heat sink, and a heat sink fan is provided on the heat sink. The heat sink fan starts when the collected temperature is greater than 40°C to quickly dissipate heat and avoid the test machine temperature being too high to affect the accuracy of the test results. In other embodiments, the heat sink 7 can also be a water-cooled heat sink, etc., which is not specifically limited.

[0051] The human-computer interaction device is arranged on the housing, including but not limited to the human-computer interaction interface 81, the mouse 82, the keyboard 83, etc. The human-computer interaction device is electrically connected to the control board 3 for displaying, storing, printing and analyzing the contact resistance test results. The user can also manually control the test process or view the test results.

[0052] In summary, the utility model provides a large-scale automated contact resistance testing machine, which can automatically and quickly test the contact resistance value of the socket, realize batch testing and rapid screening, improve test efficiency, and reduce test errors caused by manual labor; the testing machine provides 1024 test channels to meet most socket testing needs, is universal and reusable, and users only need to replace the test substrate according to different test sockets. For small package sockets, some test channels of the machine can be flexibly selected; the contact resistance range that can be measured by the testing machine is 0-800 milliohms, covering most of the contact resistance values ​​of the socket pins; the testing machine provides 3 different gear measurement circuits for each test channel, and automatically switches the measurement gear according to the actual measured contact resistance value to improve the measurement accuracy.

[0053] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0054] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A large-scale automated contact resistance test machine, characterized in that: include: shell; Machine frame: the machine frame is arranged in the shell; Control board; the control board includes a high-precision constant current source, a test probe, a voltage detection circuit, and a control circuit. The high-precision constant current source is transmitted to the test channel of the substrate through the test probe to provide a constant current source for the contact resistance value of each chain, thereby converting the contact resistance of each chain into a voltage signal; Positioning device; the positioning device is arranged on the machine frame, the positioning device comprises four positioning pins adapted to the substrate, the positioning pins are provided with a position sensor, and the position sensor is electrically connected to the control board; A warning device; the warning device comprises a red indicator light, a green indicator light, and an orange indicator light arranged on the housing, and the warning device is electrically connected to the control panel; Motion device; the motion device includes a load-bearing tray, a motion plane, a positioning axis, a motion axis, a power source and a distance sensor. The load-bearing tray is fixed below the control panel, and the motion plane is fixed below the load-bearing tray. A plurality of distance sensors are installed below the motion plane. The positioning axis and the motion axis are perpendicular to the motion plane to respectively realize the positioning and motion functions. The power source provides the motion axis with clockwise and counterclockwise rotation power, thereby driving the motion plane to move up and down. During the upward movement of the motion plane, the distance sensor collects the moving distance of the motion plane in real time by detecting the distance between the motion plane and the bottom of the test machine, and transmits the collected moving distance data to the control panel; when the moving distance value is less than 64cm, the control panel controls the motion plane to continue to move up, otherwise it stops moving; Heat dissipation device; the heat dissipation device is arranged below the moving plane, and the control board collects the temperature on the board and the temperature inside the machine frame. When the collected temperature is greater than 40°C, the control board starts the heat dissipation device, otherwise it turns off the heat dissipation device, thereby reducing the measurement error caused by the change of resistance value caused by heat; Human-computer interaction device; the human-computer interaction device is arranged on the housing, the human-computer interaction device is electrically connected to the control panel, and is used to display, store, print, and analyze the contact resistance test results. The user can also manually control the test process or view the test results. The human-computer interaction device includes a human-computer interaction interface, a mouse, and a keyboard; Among them, the control board collects the state of the position sensor to detect the installation state of the substrate. When the detection state is that the installation is correct, the control board lights up the orange indicator light, sends an upward movement signal to start the movement device to move upward, and the test probe is connected to the substrate test channel. Each group of test channels has a status detection pin connected to the test probe. The control board detects the level change of the status pin of each group of test channels. When the status pin level is 3.3±0.3V, the control board provides a constant current source for the group of test channels. When the status pin level is not 3.3±0.3V, the group of tests is not powered and the alarm information is transmitted to the human-computer interaction interface display; when the detection state is not that the installation is correct, the red indicator light is lit and the alarm information is transmitted to the human-computer interaction interface display, and the movement device is not started; the control board provides a constant current to the substrate through the detection test probe, and transmits the voltage across the contact resistance of each chain on the substrate to the voltage detection circuit.

2. The large-scale automated contact resistance tester according to claim 1, characterized in that: The voltage detection circuit is an amplification circuit in which the voltage of each chain of the substrate corresponds to three amplification factors.

3. The large-scale automated contact resistance tester according to claim 1, characterized in that: The distance measuring sensor is a laser distance measuring sensor.

4. The large-scale automated contact resistance tester according to claim 1, characterized in that: The positioning shaft is a polished rod, and the moving shaft is a worm rod.

5. The large-scale automated contact resistance tester according to claim 1, characterized in that: The power source is a motor.

6. The large-scale automated contact resistance tester according to claim 1, characterized in that: The heat dissipation device is a heat sink.

7. The large-scale automated contact resistance tester according to claim 1, characterized in that: The high-precision constant current source is a 1024-channel high-precision constant current source, and the voltage detection circuit is a 1024-channel voltage detection circuit.

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