CN204347173U - High speed on off test system - Google Patents

Abstract

The utility model relates to a high-speed on-off testing system. Including test box, adapter, upper computer and output device; the input end of the test box is connected to the device under test through the adapter; the input end of the upper computer is connected to the output end of the test box, and the output end of the upper computer is connected to the output device; the upper computer includes The test preparation unit and the test unit; the test box includes a motherboard, a switch matrix board group connected through the motherboard and a resistance test unit; the test preparation unit is connected to the resistance test unit through a 16-way high-speed AD acquisition card. The utility model provides a high-speed on-off testing system with high testing speed, high resistance measuring precision and convenient operation.

Description

High Speed Continuity Test System

technical field

The utility model belongs to the field of automatic testing and relates to a testing system, in particular to a high-speed on-off testing system.

Background technique

With the in-depth refinement of the research and development work of technicians and in order to meet the research and development needs of some large and medium-sized equipment, more and more technicians need to know the connection relationship of various points inside the equipment. Manually testing the connection relationship can meet the needs of a small number of points and some small devices. For devices with a large number of test points, it is almost impossible to manually complete the traversal of the connection points, and automated test equipment must be used. At present, it is a very tedious task to test the wiring relationship manually by point-to-point. Some existing continuity testers have many problems such as slow test speed, low measurement accuracy, inconvenient use, and high price, which cannot meet the current actual needs.

Utility model content

In order to solve the technical problems existing in the background technology, the utility model proposes a high-speed on-off test system, through which the connection relationship of equipment can be detected quickly and accurately.

The technical scheme of the utility model is: a high-speed on-off test system, including a test box, an adapter, a host computer and an output device; the input end of the test box is connected to the device under test through an adapter; The output terminal of the box is connected, and the output terminal of the host computer is connected with the output device; the above-mentioned host computer includes a test preparation unit and a test unit; the above-mentioned test box includes a motherboard and a switch matrix board group connected through the motherboard and a resistance test unit; the above-mentioned The test preparation unit is connected to the resistance test unit through a 16-way high-speed AD acquisition card; its special feature is that the above-mentioned test unit is connected with the switch matrix board group through the RS485 communication unit; the above-mentioned switch matrix board group includes at least one switch matrix board; the above-mentioned switch The matrix board includes the control unit MUC, RS485 communication circuit, switch matrix circuit, decoding latch circuit, interface circuit and power supply circuit; the above control unit MUC performs data interaction with the host computer through the RS485 communication circuit; the above switch matrix circuit and the decoding The latch circuit is connected to the interface circuit, and is connected to the control unit MUC through the decoding latch circuit, and connected to the device under test through the interface circuit; the above-mentioned switch matrix board also includes a control switch, and the above-mentioned control switch is an analog switch DG2731DQ;

The above-mentioned output devices include monitors and printers;

The model of the above 16-channel high-speed AD acquisition card is ADLINK 9114.

The utility model has the advantages that: the utility model has a fast on-off test speed, and the high-speed on-off test system can be used to realize high-speed measurement of the tested part, and the speed can reach 1000 times per second; the precision of the resistance value measurement is high, and the on-off The resistance measurement error of the resistor is less than 5‰; the test software is easy to operate and easy to learn. The test results are composed of indicator lights and reports. It is clear at a glance whether there is a fault. The test report is saved in the computer in EXCEL format, which is convenient for future viewing and proofreading.

1. High test speed: Compared with traditional applications, this utility model replaces the original relay switch with a high-speed analog switch. The switch closing time of the relay is about 4-6 milliseconds, and the closing and opening time of the high-speed analog switch is about 0.08 milliseconds, which is much smaller than the parameters of the relay. Therefore, the use of high-speed analog switches can greatly improve the test speed, and easily realize the test of 1000 test points per second.

2. High resistance measurement accuracy: the utility model has 6 resistance measurement gears for users to choose, and the maximum ranges are: 500 ohms, 5K, 50K, 500K, 1.4M and 3.5M. Due to the use of pre-calibration technology, the on-resistance of connectors, wires and switches is pre-tested and this value is subtracted from the test results, so that the measurement accuracy of the resistance value is better than 0.5%.

3. Convenient operation: The utility model adopts a brand-new human-computer interaction interface, which is friendly and easy to operate; the connection of the test equipment is equipped with a special adapter plug, which is convenient for users to quickly connect the test equipment.

Description of drawings

Figure 1 Schematic diagram of the structure of the high-speed on-off test system;

Figure 2 is the frame diagram of the resistance test unit

Detailed ways

A high-speed on-off test system, including a test box, an adapter, a host computer and an output device; the input end of the test box is connected to the device under test through an adapter; the input end of the host computer is connected to the output end of the test box, and the output end of the host computer Connect with the output device; the upper computer includes a test preparation unit and a test unit; the test box includes a motherboard and a switch matrix board group connected through the motherboard and a resistance test unit; the test preparation unit passes 16 high-speed AD acquisition cards and resistance test Unit connection; the test unit is connected to the switch matrix board group through the RS485 communication unit; the switch matrix board group includes at least one switch matrix board; the switch matrix board includes a control unit MUC, an RS485 communication circuit, a switch matrix circuit, a decoding latch circuit, and an interface circuit and power supply circuit; the control unit MUC performs data interaction with the upper computer through the RS485 communication circuit; the switch matrix circuit is respectively connected with the decoding latch circuit and the interface circuit, and is connected with the control unit MUC through the decoding latch circuit Connect with the device under test; the switch matrix board also includes a control switch, the control switch is an analog switch DG2731DQ; the output device includes a monitor and a printer; the model of the 16-channel high-speed AD acquisition card is ADLINK 9114. The test box realizes the connection and measurement with each test point of the DUT through the adapter; the host computer receives the measured value from the test box and processes the data, and transmits the processed data to the output device for display. Among them, the power supply circuit supplies power to several other module circuits. The MCU is the control module of the switch matrix board. It performs data interaction with the host computer through the RS485 communication circuit. The switch matrix circuit is the core circuit of the switch matrix board. Connected to the device under test through the interface circuit.

The invention changes the switching devices in traditional applications from relays to high-speed analog switches. The latter is small in size and short in closing and breaking time, which can greatly improve the test speed; the switch matrix structure is modified, and the switches of each node are completely independent and easy to control. And it can realize the calibration and zeroing of the resistance value before the measurement, so as to improve the measurement accuracy of the resistance value.

Develop a high-speed on-off test system, which can not only realize high-speed measurement of the connection relationship of the measured points, but also obtain the conduction resistance value between points, and is easy to operate and use. The high-speed continuity test system consists of four parts: test box, adapter, host computer and output device. The entire test system completes the on-off situation and specific resistance measurement of each test point of the DUT; the adapter is used to connect the DUT and the test system; the test box realizes the connection and measurement of each DUT point ;The upper computer module receives the measured value from the test box and processes the data to obtain the final test report; the output device displays the result.

The key point of the test system is the high-speed test of the on-off situation between the points of the tested chassis, and when required, measure the resistance value between points, so the design focus is on the test box.

The test box is composed of switch matrix board and AD acquisition board. These two parts are connected through the motherboard in the test box. Among them, there are 16 switch matrix boards, each of which can be connected to 64 test points and 1 AD acquisition board. . The switch matrix board is composed of a MCU, switch matrix circuit, power supply circuit, RS485 communication circuit, decoding latch circuit and interface circuit; the switch matrix circuit is the core circuit, in order to realize the high-speed measurement of the on-off relationship, the switch matrix board The switch uses the analog switch DG2731DQ, which is small in size and has a short on-off time. The current similar products use relays. The switching speed of the relay is slow and the volume is large. It is impossible to achieve one-to-one correspondence between test points and switches. These all limit its testing speed. The MCU receives the test command from the host computer, and controls the switch matrix circuit through decoding and latching to realize the function of connecting the measured point to the test system. The AD acquisition board is composed of a reference power supply circuit, a measurement circuit, an amplification circuit, a gear change circuit and an interface circuit.

After receiving the voltage signal from the AD acquisition board, the upper computer module processes it, including two parts, one is the pre-test preparation module, and the other is the test module. The pre-test preparation module provides the necessary conditions for the work of the test module, and the test module realizes the measurement of the DUT.

In addition, by replacing a set of adapters (connecting the test system and the PCB board), the high-speed on-off test system can be used for PCB copying work, which can greatly reduce the workload of reverse designers, and the current software system can be modified slightly. It realizes one step from copying the board to drawing the schematic diagram, which greatly improves the work efficiency of the designer and reduces the tedious and repetitive work. The speed of the continuity test is fast, and the high-speed continuity test system can be used to realize the high-speed measurement of the tested part, and the speed can reach 1000 times per second; the precision of the resistance measurement is high, and the resistance measurement error of the on-resistance is less than 5‰;

The test software is easy to operate and easy to learn. The test results are composed of indicator lights and reports. It is clear at a glance whether there is a fault. The test report is saved in the computer in EXCEL format, which is convenient for future viewing and proofreading.

The adapter is made according to the interface of the DUT, and the DUT connects all the points to be tested to the test box through it.

The 16 switch matrix boards of the switch matrix module receive the test command from the host computer at the same time, and control the analog switch action according to the command, and introduce the two test points currently to be tested into the AD resistance measurement module.

The AD resistance measurement module measures the voltage value of two connected points according to the principle of resistance voltage division, and the upper computer calculates the resistance value of the connected resistance according to the voltage value; in order to improve the accuracy of the measurement result, the AD acquisition board will be When the voltage between the two points is measured and sent to the host computer, the reference voltage is also connected to the host computer, and the measured point is measured by the multi-level measurement method. The change of gears is controlled by the software of the host computer. The final result is directly read on the host computer.

The RS485 communication module is used to realize the data and command transmission between the upper computer and the test box.

The ADLINK 9114 acquisition card completes the acquisition and reading of the measured voltage on the AD acquisition board.

The test preparation module is a part of the test software, which mainly completes the preparation work before the test, including three modules: equipment self-inspection, test table generation and equipment line resistance measurement. The equipment self-inspection conducts a comprehensive inspection of the communication of the test system, the analog switch of the switch matrix board, and the AD acquisition board to ensure that everything in the test system is normal before proceeding to the next step of detection; the module of generating test tables prepares for the self-study test. The number of test points of the DUT can generate a test table that completely traverses these points; the measurement equipment line resistance module measures the resistance value introduced by the system itself, which can improve the accuracy of on-resistance measurement.

The test module is a part of the test software, including self-learning test, continuity test and resistance test. The self-learning test detects a non-faulty DUT according to the test table generated before, and records its on-off relationship table as the basis for measuring the connection relationship of the same type of DUT; the on-off test is based on the self-study results. The connection relationship of the same type of DUT is tested, and the test point pairs with incorrect connection relationship are recorded; the resistance test is to test the specific resistance value of the conduction point, and judge whether the conduction resistance value exceeds its specified range.

The result is output through the display, if there is a fault in the test, the fault indicator light will be on, and the user can get the data of the faulty test point by viewing the test report saved as an EXCEL table.

The data processing process includes taking the average value of the test results, processing the resistance value of every two test points minus the wire resistance (excluding the influence of the resistance value on the wire and connector) and comparing with the self-learning result (the self-learning process is to test a fault-free device on-off relationship, and save the data).

Claims (3)

1. A high-speed on-off test system, comprising a test box, an adapter, a host computer and an output device; the input of the test box is connected to the device under test through an adapter; the input of the host computer is connected to the output of the test box Connect, the host computer output terminal is connected with the output device; The host computer includes a test preparation unit and a test unit; The test box includes a motherboard and a switch matrix board group and a resistance test unit connected through the motherboard; The test The preparation unit is connected with the resistance test unit through 16 high-speed AD acquisition cards; it is characterized in that: the test unit is connected with the switch matrix board group through the RS485 communication unit; the switch matrix board group includes at least one switch matrix board; the switch The matrix board includes a control unit MUC, an RS485 communication circuit, a switch matrix circuit, a decoding latch circuit, an interface circuit and a power supply circuit; the control unit MUC performs data interaction with the upper computer through the RS485 communication circuit; the switch matrix circuit communicates with the upper computer respectively The decoding latch circuit is connected to the interface circuit, and is connected to the control unit MUC through the decoding latch circuit, and is connected to the device under test through the interface circuit; the switch matrix board also includes a control switch, and the control switch is an analog switch DG2731DQ . 2. A high-speed on-off test system according to claim 1, wherein the output device includes a display and a printer. 3. A kind of high-speed on-off test system according to claim 2, characterized in that: the model of the 16-way high-speed AD acquisition card is ADLINK 9114.