CN215986249U

CN215986249U - Voltage and waveform measuring device

Info

Publication number: CN215986249U
Application number: CN202120196423.0U
Authority: CN
Inventors: 刘江涛; 王震; 魏丽; 彭雪萍; 刘汪; 杨巍; 王军
Original assignee: Wuhan Huazhong Numerical Control Co Ltd
Current assignee: Wuhan Huazhong Numerical Control Co Ltd
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2022-03-08
Anticipated expiration: 2031-01-25

Abstract

A voltage and waveform measuring device comprises a testing bottom plate, and a voltage measuring plate and a waveform measuring plate which are arranged on the testing bottom plate, wherein the voltage measuring plate comprises a voltage signal input unit, a voltage signal conditioning unit, an A/D (analog/digital) conversion unit, a first programmable controller and a first data communication unit which are sequentially and electrically connected; the waveform measuring plate comprises a waveform signal input unit, a waveform signal conditioning unit, a waveform shaping unit, a second programmable controller and a second data communication unit which are electrically connected in sequence; the test bottom plate comprises a test voltage input interface, a waveform signal input interface and a 485 communication interface, the test voltage input interface is electrically connected with the voltage signal input unit, the waveform signal input interface is electrically connected with the waveform signal input unit, and the first data communication unit and the second data communication unit are electrically connected with the 485 communication interface.

Description

Voltage and waveform measuring device

Technical Field

The utility model relates to the field of testing, in particular to a voltage and waveform measuring device.

Background

When the electronic product is subjected to charged detection, the detection of voltage and waveform occupies a great proportion, and the method is also an extremely important standard for judging whether the product performance is qualified or not. At present, the voltage and waveform test in the market generally adopts a manual instrument detection mode or a special test equipment development test mode. The manual instrument detection mode needs to consume a great deal of time of a tester, and also needs to buy expensive test instruments; development of a test mode for a dedicated test device requires investment in development cost and time. The detection efficiency of the manual instrument detection mode is low, and the manual instrument detection mode is not suitable for testing large-batch board cards; the development of a test mode of special test equipment needs investment in development cost and time, and the method has poor universality and narrow application range. Therefore, it is very meaningful to design a voltage and waveform measuring module which is convenient, fast, automatic and wide in application range to test the voltage and waveform of a product.

SUMMERY OF THE UTILITY MODEL

In view of the technical drawbacks and disadvantages of the prior art, embodiments of the present invention provide a voltage and waveform measuring device that overcomes or at least partially solves the above problems, and includes:

a voltage and waveform measuring device is characterized by comprising a test base plate, and a voltage measuring plate and a waveform measuring plate which are arranged on the test base plate, wherein the voltage measuring plate comprises a voltage signal input unit, a voltage signal conditioning unit, an A/D conversion unit, a first programmable controller and a first data communication unit; the waveform measuring plate comprises a waveform signal input unit, a waveform signal conditioning unit, a waveform shaping unit, a second programmable controller and a second data communication unit, wherein the waveform signal input unit, the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller and the second data communication unit are electrically connected in sequence; the test bottom plate comprises a test voltage input interface, a waveform signal input interface and two 485 communication interfaces, wherein the test voltage input interface is electrically connected with the voltage signal input unit, the waveform signal input interface is electrically connected with the waveform signal input unit, and the two 485 communication interfaces are respectively electrically connected with the first data communication unit and the second data communication unit.

The voltage signal input unit is used for connecting a voltage signal to the measuring module. During measurement, a voltage signal to be measured is directly connected to the test voltage input interface seat on the test bottom plate through a wire. The utility model is suitable for application test occasions with voltage signals lower than 40V, and a test voltage input interface seat on a bottom plate has 12 wiring ports in total, and 6 groups of voltages can be accessed simultaneously (the positive electrode and the negative electrode of the voltage are accessed by one terminal respectively).

The voltage signal conditioning unit is used for reducing and conditioning the input voltage signal, so that the processing of the A/D conversion unit at the rear stage is facilitated, the damage to the rear-stage circuit or the exceeding of the maximum range of the A/D conversion unit due to overlarge voltage is prevented, 1/20 reduction processing is uniformly performed, namely, the input voltage is reduced to 1/20 of the original size, the maximum range of the system is 40V, and the maximum voltage input to the rear-stage measurement unit after the conditioning is performed is 2V.

The A/D conversion unit is used for converting the analog voltage signal into a digital signal, and the digital signal is processed by the first programmable controller, so that the amplitude of the voltage can be obtained through calculation.

The first programmable controller is used for controlling the A/D conversion unit primary data communication unit; the method comprises the steps of controlling an AD chip to perform analog-to-digital conversion, and reading a voltage test result; and controlling the first data communication unit, and uploading the voltage test result to PC upper computer software for displaying.

The first data communication unit is used for uploading the measured data to PC upper computer software, the utility model is realized through RS485 standard communication interface, only need test bottom plate connect a USB to 485 converter externally, can realize the data transmission of the measuring module and PC.

The waveform signal input unit is used for connecting a waveform signal into the measuring module, and during measurement, a voltage signal to be measured is directly connected into the waveform signal input interface seat on the testing bottom plate through the radio frequency connecting wire.

The waveform signal conditioning unit comprises a frequency dividing circuit and an amplitude amplifying/reducing circuit, wherein the amplitude amplifying/reducing circuit is used for amplifying or reducing the waveform amplitude to a proper test range, otherwise, the waveform voltage amplitude is too large and the circuit is damaged; the frequency dividing circuit is used for reducing the waveform frequency range to a proper test range, and if the waveform frequency is too large, the programmable controller cannot normally test and process waveforms.

The waveform shaping unit is used for converting the input main periodic signal waveform such as sine, triangle, square wave and the like into a square wave signal for the second programmable controller to process and calculate to obtain the frequency and the duty ratio of the square wave signal.

The second programmable controller is used for controlling the waveform shaping unit and the data communication unit; the method comprises the steps of processing a waveform signal output by a waveform shaping unit, calculating the frequency and the duty ratio of a square wave signal, controlling a data communication unit, and uploading a voltage test result to PC upper computer software for displaying.

The second data communication unit is used for uploading measured waveform data to PC upper computer software, and the measurement is realized through an RS485 standard communication interface, and only a USB-to-485 converter is required to be externally connected to the measurement bottom plate, so that data transmission between the measurement module and the PC can be realized.

The voltage measuring board further comprises a first isolation power supply unit, the waveform measuring board further comprises a second isolation power supply unit, the test bottom board further comprises a power supply voltage interface, the first isolation power supply unit and the second isolation power supply unit are electrically connected with the power supply voltage interface, the first isolation power supply unit is respectively and electrically connected with the voltage signal input unit, the voltage signal conditioning unit, the A/D conversion unit, the first programmable controller and the first data communication unit, and the second isolation power supply unit is respectively and electrically connected with the waveform signal input unit, the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller and the second data communication unit.

The first isolation power supply unit is used for providing power supply voltage for the voltage signal conditioning unit, the A/D conversion unit, the programmable controller unit and the data communication unit in the voltage measuring plate. The first isolation power supply unit supplies power to the unit circuit by using a B0505XT-1WR2CDC power supply module, so that the reference ground of the voltage signal conditioning unit, the A/D conversion unit, the first programmable controller unit and the first data communication unit of the whole voltage measuring board is consistent with the reference ground of the input test voltage.

The second isolation power supply unit is used for providing power supply voltage for the waveform signal conditioning unit, the waveform shaping unit, the programmable controller unit and the data communication unit in the waveform measuring plate. The second isolation power supply unit supplies power to the unit circuit by using a B0505XT-1WR2CDC power supply module, so that the reference ground of the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller unit and the second data communication unit of the whole waveform measuring board is consistent with the reference ground of the input test waveform.

The test baseboard can be simultaneously inserted with six voltage measurement boards and six waveform measurement boards, namely 6 paths of voltage and 6 paths of waveforms can be tested at most simultaneously. Every measurement board is connected through a 20 PIN's seat with the test bottom plate, reach the effect of power supply and transmission signal, wherein, test bottom plate total two supply voltage interface, two 485 communication interfaces, two supply voltage interface electricity are connected, two 485 communication interfaces are also connected electrically, the purpose of setting up two interfaces is that the module cascades the use, can cascade together a plurality of measurement module, only need to link together supply voltage interface and 485 communication interface on each measurement module bottom plate, just can, for example, need test 12 way voltages, just can cascade together 2 measurement module uses.

When the single module is used, an external power supply is connected to a power supply voltage interface, the 485 communication interface is connected with a USB interface of a PC through a USB-to-485 converter, and voltage and waveform test results of all paths can be obtained by running test software on the PC. The communication protocol can be customized, and a modbus communication protocol can also be used. This example uses a custom communication protocol, protocol type: the sending instruction is frame head + instruction + check sum + frame tail, the frame head is 0XAA, the instruction is composed of length code (total length of instruction part), command code (11 represents voltage, 22 represents waveform), address code (group number of voltage measuring board or waveform measuring board), the check sum has two bytes, which are respectively high-order and low-order bytes after summation calculation of length code, command code and address code. The end of frame is 0XFF, indicating the end of a frame of data. For example, (1) the PC software sends AA 0311010015 FF to obtain the voltage value of the first voltage measurement board, the first voltage measurement board receives the command and sends AA 051101 VH VL SH SL FF to the upper computer, VH VL indicates the high order and the low order of the voltage value, SH SL indicates the high order and the low order of the checksum, if the voltage value is 5.125V, the voltage value is multiplied by 1000 corresponding decimal number 5125, and the 16-system number is converted into 0x1405, then VH is 0x14, VL is 0x05, the PC software only needs to obtain the value of VH VL, the decimal number is 5125, and the voltage value is 5.125V by dividing the calculated value by 1000 (the final calculated value needs to be divided by 1000 for all voltage measurement modules to be the final measured value). (2) Sending AA 0322010026 FF by PC software to obtain the frequency value and duty ratio value of the first waveform measuring board (the board address code is 01), sending AA 091101 FH FL FW DY DL DW SH SL FF to the upper computer after the first waveform measuring board receives the command, wherein FH FL DH DL respectively represents the high bit and the low bit of the frequency and the duty ratio, SH SL respectively represents the high bit and the low bit of the effective data checksum, FW represents the data width control bit of the frequency, when FW is 1, the frequency value calculated by FH FL is multiplied by 10, when FW is 3, the frequency value calculated by FH FL is multiplied by 1000, when FW is 0, the frequency value calculated by FH FL is multiplied by 1; DW represents a data width control bit of the duty ratio, which means that the frequency value calculated by FH FL is multiplied by 0.1 when DW is 1, 0.001 when DW is 3, and 1 when DW is 0; this example returns AA 09110127100013880200 EF FF; the PC software only needs to obtain FH FL FW DH DL DW values and then performs conversion to obtain the frequency (0x27 × 256+0x10) × 1 ═ 10000(Hz) and the duty ratio (0x13 × 256+0x88) × 0.01 ═ 50 (%).

When a plurality of modules are used, the power supply voltage interface and the 485 communication interface on the bottom plate of each measuring module are required to be connected together, then the power supply voltage interface of any measuring module is selected to be connected with the power supply switch power supply, and the 485 communication interface is externally connected with a USB-to-485 converter to be connected with a PC. The address codes of the voltage measurement board modules are different, and the address codes of the waveform measurement boards are different, so that when the PC sends different instruction codes and address codes, the unique corresponding measurement board responds to the different instruction codes and address codes, corresponding test data is returned, and communication conflict cannot be sent. The main control MCU is arranged on each measuring board, programs of the MCU are different, and mainly address codes and function codes in MCU testing programs are different. All voltage measuring boards connected into one measuring module have the same function code and different address codes; all the waveform measuring boards accessed into one measuring module have the same function code and different address codes.

Further, the first isolation power supply unit and the second isolation power supply unit both comprise a B0505XT-1WR2CDC power module chip and a peripheral circuit thereof.

Further, the first programmable controller and the second programmable controller are both programmable controllers based on an FPGA or an MCU.

Further, the voltage signal conditioning unit comprises a TLV2372 operational amplifier chip and a peripheral circuit thereof, and is used for scaling and conditioning the voltage signal output by the voltage signal input unit.

Further, the a/D conversion unit includes a TLC7135 chip and its peripheral circuit, which is used to convert the analog voltage signal output by the voltage signal conditioning unit into a digital signal, and the TLC7135 chip is a monolithic 4-1/2 bit a/D converter manufactured by CMOS process, and has a full scale of 2V.

Further, the waveform shaping unit comprises a 74LS90 chip and peripheral circuits thereof, and is used for converting the signal waveform input by the waveform signal conditioning unit into a square wave signal.

The utility model has the following beneficial effects:

1. the utility model adopts a modularized measuring mode, the type and the number of the measuring board cards on the measuring module can be freely selected by a user, and the user can realize the accurate connection with the measuring module only by introducing signals into a bottom plate of the measuring module and inserting the measuring board cards with the corresponding type and the number, so the utility model has wide application range and high testing efficiency;

2. the special voltage test circuit and the waveform test circuit are adopted to test the signal parameters, and the test result is reliable and accurate.

3. RS485 is adopted for communication, a flexible user-defined communication protocol is adopted, and data reading of all the measuring board cards can be realized only by connecting two communication lines.

4. When the number of signals tested by a user is large, the measuring modules can be expanded and cascaded, a plurality of modules are connected together, only the power supply voltage interface and the 485 communication interface on the bottom plate of each measuring module are connected together, then the power supply voltage interface of any measuring module is selected to be connected with the power supply switch power supply, and the 485 communication interface is connected with the PC machine, so that the power supply and communication functions of all the functional modules can be realized.

5. The measuring module of the utility model has compact structure, convenience, flexibility and simple operation, and can meet the individual test requirements of users.

Drawings

FIG. 1 is a block diagram of a voltage and waveform measuring device provided by an embodiment of the present invention;

fig. 2 is a circuit structure diagram of a voltage measuring board according to an embodiment of the present invention;

fig. 3 is a circuit structure diagram of a waveform measuring board according to an embodiment of the present invention;

FIG. 4 is a schematic circuit diagram of an isolated power supply unit according to an embodiment of the present invention;

fig. 5 is a schematic circuit diagram of a data communication unit according to an embodiment of the present invention;

FIG. 6 is a schematic circuit diagram of a voltage signal conditioning and A/D conversion unit according to an embodiment of the present invention;

fig. 7 is a schematic circuit diagram of a waveform signal conditioning and shaping unit according to an embodiment of the present invention.

In the figure: the voltage measuring device comprises a 1-voltage signal input interface, a 2-waveform signal input interface, a 3-voltage measuring board slot, a 4-waveform measuring board slot, a 5-voltage measuring board, a 6-waveform measuring board, a 7-power supply voltage interface, an 8-485 communication interface and a 9-positioning mounting hole.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a schematic overall structure diagram of a board card automatic measurement module based on a desktop multimeter according to the utility model. As shown in fig. 1, the measurement apparatus according to the preferred embodiment of the present invention mainly includes a voltage signal input interface 1(6 groups), a waveform signal input interface 2(6 groups), voltage measurement board slots 3 (6), waveform measurement board slots 4 (6), a voltage measurement board 5 (a single module is connected to 6 blocks at most), a waveform measurement board 6 (a single module is connected to 6 blocks at most), a power supply voltage interface 7 (2), 485 communication interfaces 8 (2), and positioning mounting holes 9 (4). The voltage signal input interface 1(6 groups) and the waveform signal input interface 2(6 groups) are used for introducing external voltage and waveform signals to be tested into the measuring module. The four units of the voltage measurement board slot 3, the waveform measurement board slot 4 and the voltage measurement board 5 and the waveform measurement board 6 are used for measuring and processing signals, and only the voltage or waveform measurement board needs to be inserted into the corresponding slot during testing; the power supply voltage interface 7 is an external power supply interface of the whole measuring module, and the 485 communication interface 8 is used for transmitting the test result to the PC upper computer. The positioning mounting holes 9 are used for mounting the entire measuring module, which can be mounted in a test fixture box when the test fixture is used by the user.

The voltage signal input unit is used for connecting a voltage signal to the measuring module, and during measurement, the voltage signal to be measured is directly connected to the test voltage input interface seat on the test bottom plate through a lead. The utility model is suitable for application test occasions with voltage signals lower than 40V, and a test voltage input interface seat on a bottom plate has 12 wiring ports in total, and 6 groups of voltages can be accessed simultaneously (the positive electrode and the negative electrode of the voltage are accessed by one terminal respectively).

The function of the a/D conversion unit is to convert an analog voltage signal into a digital signal, and the digital signal is processed by the first programmable controller, so that the magnitude of the voltage can be calculated, and the circuit schematic diagram of the voltage signal conditioning unit and the a/D conversion unit is shown in fig. 4.

The waveform signal conditioning unit comprises a frequency dividing circuit and an amplitude amplifying/reducing circuit, wherein the amplitude amplifying/reducing circuit is used for amplifying or reducing the waveform amplitude to a proper test range, otherwise, the waveform voltage amplitude is too large and the circuit is damaged; the frequency dividing circuit is used for reducing the waveform frequency range to a proper test range, and if the waveform frequency is too large, the programmable controller cannot normally test and process the waveform.

The waveform shaping unit is used for converting the input main periodic signal waveform such as sine, triangle, square wave and the like into a square wave signal, and the square wave signal is processed by the second programmable controller and the frequency and the duty ratio of the square wave signal are obtained through calculation, as shown in fig. 5, the waveform shaping unit is a specific circuit schematic diagram of the waveform signal conditioning and shaping unit provided by the embodiment.

The second data communication unit is used for uploading measured waveform data to the PC upper computer software, and this example is implemented by an RS485 standard communication interface, and only a USB to 485 converter is externally connected to the measurement backplane, and data transmission between the measurement module and the PC can be implemented, where the first data communication unit and the second data communication unit have the same circuit principle, as shown in fig. 6, which is a specific circuit principle diagram of the data communication unit provided in this embodiment.

The first isolation power supply unit is used for providing power supply voltage for the voltage signal conditioning unit, the A/D conversion unit, the programmable controller unit and the data communication unit in the voltage measuring plate. The first isolation power supply unit supplies power to the unit circuit by using a B0505XT-1WR2CDC power module, so that the reference ground of the voltage signal conditioning unit, the a/D conversion unit, the first programmable controller unit, and the first data communication unit of the entire voltage measurement board is consistent with the reference ground of the input test voltage, wherein the circuit principle of the first isolation power supply unit and the second isolation power supply unit is the same, as shown in fig. 7, a specific circuit principle diagram of the isolation power supply unit provided in this embodiment is provided.

The test baseboard can be simultaneously inserted with six voltage measurement boards and six waveform measurement boards, namely, six voltages and six waveforms can be simultaneously tested at most. Every measurement board is connected through a 20 PIN's seat with the test bottom plate, reach the effect of power supply and transmission signal, wherein, test bottom plate total two supply voltage interface, two 485 communication interfaces, two supply voltage interface electricity are connected, two 485 communication interfaces are also connected electrically, the purpose of setting up two interfaces is that the module cascades the use, can cascade together a plurality of measurement module, only need to link together supply voltage interface and 485 communication interface on each measurement module bottom plate, just can, for example, need test 12 way voltages, just can cascade together 2 measurement module uses.

Fig. 2 is a schematic diagram illustrating a voltage measurement operating principle of a measurement module according to an embodiment of the present invention, and fig. 3 is a schematic diagram illustrating a waveform measurement operating principle of a measurement module according to an embodiment of the present invention, which is for convenience of description, in combination with an operating process according to an embodiment of the present invention, detailed below:

a power supply voltage source is led to a power supply voltage interface 7 of the measuring device through a power line, and a voltage signal to be tested is connected to a voltage signal input interface 1 of the measuring device; the waveform signal to be tested is accessed into a waveform signal input interface 2 of the measuring device; inserting the voltage measurement board 5 into the voltage measurement board slot 3; inserting the waveform measuring plate 6 into the waveform measuring plate slot 4; the 485 communication interface 8 is externally connected with a USB-to-485 converter and is connected with a PC; the whole measuring device is arranged in the test fixture box through the positioning mounting hole. And after the connection is finished, running the test software installed on the PC host. The PC host sends different communication instruction codes to the measuring device to read the measuring data of the measuring device.

Taking the test of a product board with a small number of test signals as an example, the product board needs to test three square wave signals of 5V, 12V, 24V, 10KHz, 50KHz, and 100 KHz. Then the test flow is as follows: introducing a power supply voltage source to a power supply voltage interface 7 of the measuring device through a power line, and connecting three voltage signals with tests to a voltage signal input interface 1 of the measuring device (selecting the left group 3 for connection); the waveform signal with test is connected to the waveform signal input interface 2 of the measuring module (the left group 3 is selected for connection); inserting the voltage measuring board 5 (the left 3 pieces) into the voltage measuring board slot 3; inserting the waveform measuring plate 6 (the left 3 blocks) into the waveform measuring plate slot 4; the 485 communication interface 8 is externally connected with a USB-to-485 converter and is connected with a PC; and then the PC software sends AA 0311010015 FF to obtain the voltage value of the first voltage measurement board on the left (the board address code is 01), the first voltage measurement board receives the command and sends AA 051101 VH VL SH SL FF to the upper computer, VH VL represents the high bit and the low bit of the voltage value, SH SL represents the high bit and the low bit of the checksum, if the voltage value is 5.125V, the multiplication is carried out by 1000 to correspond to decimal number 5125, and the conversion is carried out to 16-system number 0x1405, then VH is 0x14, VL is 0x05, the PC software only needs to obtain the value of VH VL, the conversion is carried out to obtain the decimal number 5125, and the division is carried out to 1000 to obtain the voltage value of 5.125V. Sending AA 0322010026 FF by PC software to obtain the frequency value and duty ratio value of the first waveform measuring board (address code of the board is 01) on the left, sending AA 091101 FH FL FW DY DL DW SH SL FF to the upper computer after the first waveform measuring board receives the command, wherein FH FL DH DL respectively represents the high bit and the low bit of frequency and duty ratio, SH SL respectively represents the high bit and the low bit of effective data checksum, FW represents the data width control bit of frequency, when FW is 1, the frequency value calculated by FH FL is multiplied by 10, when FW is 3, the frequency value calculated by FH FL is multiplied by 1000, and when FW is 0, the frequency value calculated by FH FL is multiplied by 1; DW represents a data width control bit of the duty ratio, which means that the frequency value calculated by FH FL is multiplied by 0.1 when DW is 1, 0.001 when DW is 3, and 1 when DW is 0; this example returns AA 09110127100013880200 EF FF; the PC software only needs to obtain FH FL FW DH DL DW values and then performs conversion to obtain the frequency (0x27 × 256+0x10) × 1 ═ 10000(Hz) and the duty ratio (0x13 × 256+0x88) × 0.01 ═ 50 (%). The rest two-path voltage and waveform test is similar to the above test, and only the address code needs to be changed into 02 and 03 when the PC sends a communication instruction. The PC host machine processes the three voltage test results and the three waveform test results, if the test values are abnormal, the test flow is immediately ended, and the test abnormality is displayed. And if the result is normal, displaying that the test result is normal.

Taking the test of a product board with a large number of test signals as an example, the product board needs to test 15 paths of voltage values and 10 paths of square wave signals. Then the test flow is as follows: 3 measuring devices are required to be cascaded together, a power supply voltage interface and a 485 communication interface on a testing bottom plate of the 3 measuring devices are connected together, then the power supply voltage interface of any one measuring device is selected to be connected with a power supply switch power supply, and a USB-to-485 converter is externally connected to the 485 communication interface of the 485 communication interface and is connected with a PC. The address codes of the voltage measurement board modules are different, the address codes of the waveform measurement boards are different, the address codes of the voltage measurement boards in the embodiment are from 0x01 to 0x0f, 15 in total, the address codes of the waveform measurement boards in the embodiment are from 0x01 to 0x0A, and 10 in total, so that when the PC sends different command codes and address codes, the unique corresponding measurement boards respond to the address codes, corresponding test data are returned, communication conflict cannot be sent, the specific test flow is the same, the PC host processes the 15 voltage test results and the 10 waveform test results, and if the test values are abnormal, the test flow is immediately ended, and abnormal test is displayed. And if the result is normal, displaying that the test result is normal.

In the voltage and waveform measuring module, the selected test circuit can meet the test requirement; but the user can still change the type and model of the programmable controller, the communication interface and the protocol according to the needs, and the voltage and waveform measuring module is not limited to the test of a single type of product, so that the measuring module is efficient, simple to operate and wide in application range.

It should be noted that the claimed solution of the present invention is in the selection and connection relationship of each hardware device, and those skilled in the art can obtain the corresponding upper program without objection when learning the hardware solution of the present application, so that the claimed solution of the present application does not relate to the improvement of the program.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A voltage and waveform measuring device is characterized by comprising a test base plate, and a voltage measuring plate and a waveform measuring plate which are arranged on the test base plate, wherein the voltage measuring plate comprises a voltage signal input unit, a voltage signal conditioning unit, an A/D conversion unit, a first programmable controller and a first data communication unit; the waveform measuring plate comprises a waveform signal input unit, a waveform signal conditioning unit, a waveform shaping unit, a second programmable controller and a second data communication unit, wherein the waveform signal input unit, the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller and the second data communication unit are electrically connected in sequence; the test bottom plate comprises a test voltage input interface, a waveform signal input interface and a 485 communication interface, the test voltage input interface is electrically connected with the voltage signal input unit, the waveform signal input interface is electrically connected with the waveform signal input unit, and the first data communication unit and the second data communication unit are electrically connected with the 485 communication interface.

2. The voltage and waveform measuring device of claim 1, wherein the voltage measuring board further comprises a first isolation power supply unit, the waveform measuring board further comprises a second isolation power supply unit, the test base board further comprises a power supply voltage interface, the first isolation power supply unit and the second isolation power supply unit are both electrically connected with the power supply voltage interface, the first isolation power supply unit is respectively electrically connected with the voltage signal input unit, the voltage signal conditioning unit, the a/D conversion unit, the first programmable controller and the first data communication unit, and provides working voltages for the voltage signal input unit, the voltage signal conditioning unit, the a/D conversion unit, the first programmable controller and the first data communication unit; the second isolation power supply unit is respectively electrically connected with the waveform signal input unit, the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller and the second data communication unit and provides working voltage for the waveform signal input unit, the waveform signal conditioning unit, the waveform shaping unit, the second programmable controller and the second data communication unit.

3. The voltage and waveform measuring device of claim 2 wherein there are two supply voltage interfaces and two 485 communication interfaces, the two supply voltage interfaces being electrically connected and the two 485 communication interfaces being electrically connected.

4. The voltage and waveform measuring device of claim 2, wherein the first and second isolated power supply units each comprise a B0505XT-1WR2CDC power module chip and its peripheral circuitry.

5. The voltage and waveform measuring apparatus as claimed in claim 1, wherein the test substrate is provided with a voltage measuring board slot and a waveform measuring board slot, the voltage measuring board is inserted into the test substrate through the voltage measuring board slot, and the waveform measuring board is inserted into the test substrate through the waveform measuring board slot.

6. The voltage and waveform measurement device of claim 1, wherein the first programmable controller and the second programmable controller are both FPGA or MCU based programmable controllers.

7. The voltage and waveform measuring device of claim 1, wherein the voltage signal conditioning unit comprises a TLV2372 operational amplifier chip and its peripheral circuits for scaling and conditioning the voltage signal output by the voltage signal input unit.

8. The voltage and waveform measuring device of claim 1, wherein the a/D conversion unit comprises a TLC7135 chip and its peripheral circuits for converting the analog voltage signal outputted from the voltage signal conditioning unit into a digital signal.

9. The voltage and waveform measuring apparatus according to claim 1, wherein the waveform signal conditioning unit includes a frequency dividing circuit for adjusting the frequency range of the waveform to a preset test range frequency and an amplitude amplifying/reducing circuit for amplifying or reducing the amplitude of the waveform to a preset test range amplitude value, an output terminal of the frequency dividing circuit is electrically connected to an input terminal of the amplitude amplifying/reducing circuit, an input terminal of the frequency dividing circuit is electrically connected to the waveform signal input unit, and an output terminal of the amplitude amplifying/reducing circuit is electrically connected to an input terminal of the waveform shaping unit.

10. The voltage and waveform measuring device of claim 1, wherein the waveform shaping unit comprises a 74LS90 chip and its peripheral circuits for converting the signal waveform inputted from the waveform signal conditioning unit into a square wave signal.