CN209841947U - Intelligent multimeter with automatic range switching function - Google Patents
Intelligent multimeter with automatic range switching function Download PDFInfo
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- CN209841947U CN209841947U CN201920398039.1U CN201920398039U CN209841947U CN 209841947 U CN209841947 U CN 209841947U CN 201920398039 U CN201920398039 U CN 201920398039U CN 209841947 U CN209841947 U CN 209841947U
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Abstract
The utility model provides an intelligent universal meter of range automatic switch-over. The utility model discloses a: the device comprises a resistance measuring module, a direct current voltage measuring module, an alternating current voltage measuring module, a capacitance measuring module, an inductance measuring module, a partial gear switching module, a range automatic switching module, an analog-to-digital conversion module, a microprocessor, a key module and a display module. The utility model discloses a range automatic switch-over, accurate measuring resistance, electric capacity, inductance, direct current voltage, alternating voltage, and system's overall measurement accuracy is high, measures that the small resistance accuracy is high, range automatic switch-over, output stability is good, has promoted the ability that present digital multimeter measured the small resistance.
Description
Technical Field
The utility model relates to an electron technology and instrument field especially involve an intelligent universal meter of range automatic switch-over.
Background
At present, the universal meter is an indispensable instrument in the electronic manufacturing industry, is also a very important tool in teaching and scientific research, and is widely used for measuring the quality state condition of electronic components and circuit parameter state condition. At present, a digital multimeter on the market generally only has the measurement functions of resistance measurement, voltage measurement, on-off sound detection and the like, but the multimeter with the measurement functions of capacitance and inductance is often high in price, the capacitance and the inductance are also one of the vital electronic components in the process of manufacturing electronic products at low cost, and a special test instrument is often adopted for measuring the capacitance and the inductance; the conventional digital multimeter generally needs to manually switch measuring ranges, when a user cannot predict a measuring signal or an element, the failure of selecting a correct gear or measuring range can cause the internal circuit of the digital multimeter to break down, so that the multimeter cannot normally work, and one gear of the conventional digital multimeter is often divided into a plurality of measuring ranges, so that the use is inconvenient; and because the technology is limited, the existing digital multimeter is not accurate in measuring the small resistance, and an external auxiliary circuit is needed to accurately measure the small resistance. Therefore, a digital multimeter capable of automatically switching ranges, which integrates capacitance measurement and inductance measurement, can accurately measure small resistance, and is urgently needed in the market.
SUMMERY OF THE UTILITY MODEL
In order to overcome the defects of the existing digital multimeter, the automatic range switching digital multimeter is provided, the measuring accuracy is high, particularly, the measuring accuracy of small resistors is higher, the work is stable, the operation speed is high, and the automatic range switching digital multimeter integrates measuring resistors, direct current voltage, alternating current voltage, capacitors and inductors into a whole.
The utility model discloses the technical scheme who adopts as follows:
the utility model provides an intelligent multimeter of range automatic switch-over which characterized in that includes: the device comprises a resistance measuring module, a direct current voltage measuring module, an alternating current voltage measuring module, a capacitance measuring module, an inductance measuring module, a partial gear switching module, a range automatic switching module, an analog-to-digital conversion module, a microprocessor, a key module and a display module;
the partial gear switching module is respectively connected with the resistance measuring module, the direct-current voltage measuring module and the alternating-current voltage measuring module in sequence through leads; the partial gear switching module, the range automatic switching module and the analog-digital conversion module are sequentially connected in series through leads; the microprocessor is respectively connected with the partial gear switching module, the range automatic switching module, the analog-to-digital conversion module, the capacitance measuring module, the inductance measuring module, the key module and the display module in sequence through leads.
Preferably, the resistance measuring module is configured to detect a magnitude of the resistance, convert the resistance value into a voltage signal, and output the voltage signal to the partial gear shifting module.
Preferably, the direct-current voltage testing module is configured to detect a magnitude of a direct-current voltage signal and output a stable direct-current voltage signal to the partial gear shifting module.
Preferably, the alternating voltage testing module is configured to detect an effective value of an alternating voltage signal and output a stable direct voltage signal to the partial gear shifting module.
Preferably, the capacitance measuring module is used for detecting the size of the capacitance, the frequency of an output signal of the module is only related to the resistance value of the circuit and the capacitance value to be detected, and the output signal is sent to the microprocessor.
Preferably, the inductance measuring module is used for detecting the size of the inductance, the frequency of the output signal of the module is only related to the capacitance value of the circuit and the inductance value to be measured, and the output signal is sent to the microprocessor.
Preferably, the partial gear control module is configured to select one of the output voltage of the output resistance measurement module, the output voltage of the direct current voltage measurement module, and the output voltage of the alternating current voltage measurement module according to a control signal generated by selecting different measurement modes, and send the selected one to the automatic range switching module.
Preferably, the automatic range switching module is used for realizing automatic range switching, selecting a range suitable for an input signal, and sending an output voltage of the module to the analog-to-digital conversion module, and the module is also used for outputting a range selection signal and sending the range selection signal to the microprocessor.
Preferably, the analog-to-digital conversion module is configured to convert the input analog voltage signal into a digital signal, and send the digital signal to the microprocessor to obtain the voltage to be measured or the resistance value of the resistor to be measured.
Preferably, the microprocessor is used for controlling the working time sequence of the analog-to-digital conversion module and obtaining digital quantity from the analog-to-digital conversion module so as to obtain corresponding values of the resistor to be tested, the direct current voltage and the alternating current voltage; and the frequency measuring module is used for measuring the frequency of signals output by the inductance measuring module and the capacitance measuring module so as to obtain the inductance to be measured and the capacitance value to be measured.
Preferably, the key module is a 4-by-4 matrix keyboard and is used for selecting a measurement mode of the digital multimeter. The display module is used for displaying the measured values in different measuring modes.
The beneficial effects of the utility model reside in that:
the utility model relates to an intelligent universal meter of range automatic switch-over, the design has made outside measuring circuit, the automatic switch-over range has been accomplished, resistance measurement, especially accurate little resistance measurement, direct current voltage measurement, alternating voltage measurement, capacitance measurement, functions such as inductance measurement, the weak point that current digital universal meter exists has been overcome, a range automatic switch-over is provided, measurement accuracy is high, especially, it is higher to measure little resistance precision, the job stabilization, collect measuring resistor, direct current voltage, alternating voltage, electric capacity, inductance digital universal meter as an organic whole.
Drawings
FIG. 1: is a block diagram of the composition module of the utility model;
FIG. 2: is a circuit diagram of a partial gear shifting module
FIG. 3: is a circuit diagram of an automatic range switching module
FIG. 4: is a resistance measurement module circuit diagram;
FIG. 5: is a circuit diagram for direct voltage measurement;
FIG. 6: is a circuit diagram of an ac voltage measurement;
FIG. 7: is a circuit diagram of a capacitance measurement module;
FIG. 8: is a circuit diagram of an inductance testing module;
FIG. 9: is a circuit diagram of an analog-to-digital conversion module;
FIG. 10: is a circuit diagram of a microprocessor peripheral interface circuit;
FIG. 11: is a circuit diagram of a display module;
FIG. 12: is a circuit diagram of the key module.
Detailed Description
In order to facilitate the understanding and implementation of the present invention for those of ordinary skill in the art, the present invention is further described in detail with reference to the accompanying drawings and examples, it is to be understood that the embodiments described herein are merely illustrative and explanatory of the present invention and are not restrictive thereof.
As shown in FIG. 1, the utility model discloses a constitute module block diagram, a range automatic switch's intelligent multimeter, a serial communication port, include: the utility model provides an intelligent multimeter of range automatic switch-over which characterized in that includes: the device comprises a resistance measuring module, a direct current voltage measuring module, an alternating current voltage measuring module, a capacitance measuring module, an inductance measuring module, a partial gear switching module, a range automatic switching module, an analog-to-digital conversion module, a microprocessor, a key module and a display module;
the partial gear switching module is respectively connected with the resistance measuring module, the direct-current voltage measuring module and the alternating-current voltage measuring module in sequence through leads; the partial gear switching module, the range automatic switching module and the analog-digital conversion module are sequentially connected in series through leads; the microprocessor is respectively connected with the partial gear switching module, the range automatic switching module, the analog-to-digital conversion module, the capacitance measuring module, the inductance measuring module, the key module and the display module in sequence through leads.
The resistance measuring module is used for detecting the size of the resistance, converting the resistance value into a voltage signal and outputting the voltage signal to the partial gear switching module. The direct-current voltage testing module is used for detecting the magnitude of a direct-current voltage signal and outputting a stable direct-current voltage signal to the partial gear switching module. The alternating voltage testing module is used for detecting the effective value of the alternating voltage signal and outputting a stable direct voltage signal to the partial gear switching module. The capacitance measuring module is used for detecting the size of the capacitance, the frequency of an output signal of the capacitance measuring module is only related to the resistance value of the circuit and the capacitance value to be detected, and the output signal is sent to the microprocessor. The inductance measuring module is used for detecting the size of the inductance, the frequency of an output signal of the module is only related to the capacitance value of the circuit and the inductance value to be detected, and the output signal is sent to the microprocessor. The partial gear control module is used for selecting one of the output voltage of the output resistance measuring module, the output voltage of the direct current voltage measuring module and the output voltage of the alternating current voltage measuring module according to control signals generated by selecting different measuring modes and sending the selected one to the automatic range switching module. The automatic range switching module is used for realizing automatic range switching, selecting a range suitable for an input signal and transmitting an output voltage of the module to the analog-to-digital conversion module, and the module is also used for outputting a range selection signal and transmitting the range selection signal to the microprocessor. The analog-to-digital conversion module is used for converting the input analog voltage signal into a digital signal and sending the digital signal to the microprocessor. The microprocessor is used for controlling the working time sequence of the analog-to-digital conversion module and obtaining digital quantity from the analog-to-digital conversion module so as to obtain corresponding to-be-detected resistance, direct current voltage and alternating current voltage values; and the frequency measuring module is used for measuring the frequency of signals output by the inductance measuring module and the capacitance measuring module so as to obtain the inductance and the capacitance to be measured. The key module is a 4-by-4 matrix keyboard and is used for selecting a measurement mode of the digital multimeter. The display module is used for displaying the measured values in different measuring modes.
The resistance measurement module is a precision current source circuit formed by AD8276 and AD 603; the direct-current voltage measuring module is selected as a voltage follower consisting of an OPA 228; the alternating voltage measurement module is selected to be a high-precision and root-mean-square direct current converter AD 637; the capacitance measuring module is selected as an NE555 oscillating circuit; the inductance measurement module is a Krason oscillating circuit in a type selection mode; the partial gear switching module adopts an AD7501 analog switch; the automatic range switching module adopts a resistor series voltage division circuit, an AD7501 analog switch and a four-voltage comparator LM 339; the analog-to-digital conversion module adopts a high-precision and low-power-consumption 16-bit serial analog-to-digital converter ADS1118 and peripheral circuits thereof; the microprocessor is selected from a high-speed FPGA with the model number of EP4CE40F23C8 under the CycloneIV series of Altera company; the key module is selected to be a 4 x 4 matrix keyboard; the display module is an OLED display panel with SH1106 as a driving chip and a 132 x 64 dot matrix.
As shown in fig. 2, the partial shift switching module is used for selecting one of an output voltage of the output resistance measurement module, an output voltage of the direct current voltage measurement module, and an output voltage of the alternating current voltage measurement module, the module is formed by an analog switch AD7501, the analog switch AD7501 has a wide input voltage performance of 0-25V, and a control port a0, a1, and EN of the analog switch AD7501 are respectively connected with IO _ B21, IO _ G18, and IO _ E14 of the microprocessor, and an input port S1, S2, and S3 of the analog switch AD7501 are respectively connected with the output voltage VR of the resistance measurement module, the output voltage VDC of the direct current voltage measurement module, and the output voltage VAC of the alternating current voltage measurement module. The measuring mode is selected through the key module, the microprocessor sends control signals to control ports A0, A1 and EN of the AD7501, and therefore the output port OUT of the AD7501 is controlled to output signals corresponding to the measuring mode to the automatic measuring range switching module.
As shown in fig. 3, the automatic range switching module is used for realizing automatic range switching, and is composed of a resistor series voltage dividing circuit, a four-voltage comparator LM339 and an 8-way analog switch AD 7501. The resistor series voltage-dividing circuit is composed of resistors R1, R2 and R3, and three output voltages V1, V2 and V3 respectively represent that the input voltage is not attenuated, is attenuated by 10 times and is attenuated by 100 times. The chip LM339 is internally provided with four comparators, wherein negative input ends of three comparators are connected with a comparison voltage of 200mV, positive input ends of the three comparators are respectively connected with V1, V2 and V3, when the positive input end voltage is higher than the comparison voltage, the OUTPUT end of the corresponding comparator will OUTPUT a high level, and when the positive input end voltage is lower than the comparison voltage, the OUTPUT end of the corresponding comparator will OUTPUT a low level. The OUTPUT terminals OUTPUT1, OUTPUT2 and OUTPUT3 of the chip LM339 are respectively connected to the control terminals A0, A1 and A2 of the 8-way analog switch AD7501, and three OUTPUT voltages V1, V2 and V3 are respectively connected to the input terminals S1, S2 and S4 of the 8-way analog switch AD 7501. When the input voltage is 0-200 mV, A0, A1 and A2 are respectively 0, 0 and 0, and the output end of the analog switch AD7501 is a signal of S1, namely V1; when the input voltage is 200 mV-2V, A0, A1 and A2 are respectively 1, 0 and 0, and the output end of the analog switch AD7501 is a signal of S2, namely V2; when the input voltage is 2V-20V, A0, A1 and A2 are respectively 1, 1 and 0, the output end of the analog switch AD7501 is a signal of S4, namely V3, the output end of the analog switch AD7501 is sent to the analog-digital conversion module, in addition, the control ends A0, A1, A2 and EN of the analog switch AD7501 are connected to the peripheral circuit ports IO _ C20, IO _ E12, IO _ H15 and IO _ A20 of the microprocessor, the microprocessor is used for controlling the work of the analog switches, obtaining a range selection signal and outputting the relevant signal to be measured to the display module.
As shown in fig. 4, the resistance measuring module measures the magnitude of the resistor and converts the resistance value into a voltage value, and the conventional current source circuit is constructed by using an operational amplifier, a resistor and other discrete devices, but has disadvantages in terms of size, precision, temperature drift and the like. So this precision current source circuit chooses for use high accuracy, low-power consumption, low-cost integrated differential amplifier AD8276, and the low imbalance, low offset current amplifier AD8603 is as feedback buffer, make the size littleer, the higher current source of performance becomes reality, in order to increase the driving force of system, AD8276 differential amplifier's output adds a triode 9013 and expands and flow, the constant current flows through on the resistance that awaits measuring, the accessible measures the voltage of the resistance that awaits measuring and learns the resistance value of the resistance that awaits measuring, voltage to the range automatic switch module on the resistance that awaits measuring of this module output.
As shown in fig. 5, the dc voltage measuring module is configured to detect a dc voltage, and is formed by a voltage follower circuit formed by an operational amplifier OPA228, the OPA228 chip is powered by +12V and-12V analog power supplies, wherein a 10k Ω resistor and a 3.3uF resistor are sequentially connected in series between an input terminal and ground, a 330k Ω feedback resistor is connected between an output terminal and a negative input terminal of the chip, a gain of the operational amplifier OPA228 is actually measured to be 1.02, and a stable dc voltage is output to the automatic range switching module.
As shown in fig. 6, the ac voltage measuring module is configured to detect the magnitude of the ac voltage, and a high-precision root-mean-square dc converter AD637 is used, where the AD637 chip is a chip developed by Analog Devices and used for measuring the effective value of the ac voltage based on an internal hardware operation circuit, and has a measurement error less than 0.1%, and has advantages of high precision, wide input frequency band, and the like. In order to ensure the measurement accuracy, the potentiometers of 50k omega and 1k omega are respectively subjected to zero setting and amplitude modulation before detection, an alternating voltage VinAC is input, and a stable effective value voltage signal is output to the automatic range switching module.
As shown in fig. 7, the capacitance measuring module is configured to detect the size of the capacitance, and an integrated chip NE555 is adopted, so that the size is small, and the NE555 timer can output continuous square waves with a specific frequency in an unstable-state operating mode. In order to ensure that the output frequency is low and the stability is ensured, 680k omega is selected to be connected between chip pins 7 and 4, 430k omega is selected to be connected between chip pins 2 and 7, a capacitor to be tested is connected between chip pins 1 and 2, and chip pin 3 outputs a stable square wave signal to a peripheral interface F _ C of the microprocessor.
As shown in fig. 8, the inductance measuring module is configured to detect a size of an inductance, and a clar oscillator circuit is an improved circuit of a capacitance three-point oscillator, where the circuit uses a 2N3904 type triode, uses 20k Ω,5.1k Ω, and 1k Ω resistors as a voltage-dividing bias resistor, uses 0.1uF and 0.01uF as a bypass and a dc blocking capacitor, and uses 1k Ω resistors as a collector dc load resistor, and in order to avoid an influence of a parasitic capacitor, a 10nF capacitor is connected in series with an inductance to be measured, and the inductance to be measured connected to the circuit from 100uH to 10mH can satisfy a start-up condition, and output a stable oscillation wave to a peripheral interface F _ L of a microprocessor.
As shown in fig. 9, the analog-to-digital conversion module is used to convert the analog voltage signal into a digital signal, and send the digital signal to the microprocessor. The module consists of a high-precision and low-power-consumption 16-bit serial analog-to-digital converter ADS1118 and peripheral circuits thereof, pins AIN0, AIN1 and AIN2 of a chip of the ADS1118 are respectively connected with 50 omega resistors in series and are respectively connected with output voltages of a resistor measuring module, a direct-current voltage measuring module and an alternating-current voltage measuring module; the pins DIN, DOUT, CS, SCLK and VDD of the ADS1118 chip are respectively connected with the pins IO _ F22, IO _ E22, IO _ D22, IO _ F20 and VCC3P3 of the microprocessor, and 0.1uF electrolytic capacitors are adopted between a power supply and the ground for decoupling.
As shown in fig. 10, the microprocessor adopts a high-speed FPGA of EP4CE40F23C8 model under the cycle IV series of Altera corporation, and includes a peripheral interface circuit, and output terminals IO _ F21, IO _ E21, IO _ D21 and IO _ F19 of the peripheral interface circuit are respectively connected to OLED SCL, OLED SDA, OLED RESET and OLED D/C of the display module; the output ends IO _ F22, IO _ E22, IO _ D22 and IO _ F20 of the peripheral interface circuit are respectively connected with DIN, DOUT, CS and SCLK of the analog-to-digital conversion module; the output end VCCIO8_ A2 of the peripheral interface circuit is connected with 3.3V voltage; the output terminal GND _ L10 of the peripheral interface circuit is connected to ground.
As shown in fig. 11, the display module is an OLED display screen, which has a size of 1.3 inches and a resolution of 128 × 64 pixels, and adopts a driver chip with a model SH1106, a 132 × 64 dot matrix OLED display panel, and a 132 × 64 bit SRAM display buffer integrated inside, and has four interfaces: and the OLED SCL, the OLED SDA, the OLED RESET and the OLED D/C are used for providing a human-computer interaction interface and displaying the measured value.
As shown in fig. 12, the key module employs a 4 × 4 matrix keyboard, which is used for assigning key values and setting different measurement modes.
The following description of the embodiments is made with reference to fig. 1 to 12:
the whole working mode of the intelligent multimeter with the automatically switched measuring range is as follows: firstly, selecting the working mode of the current multimeter through a display module and a key module, wherein the total five modes are as follows: resistance measurement, alternating voltage measurement, direct voltage measurement, capacitance measurement and inductance measurement, wherein the mode internal range is automatically switched; secondly, after the working mode is selected, if resistance measurement, direct current voltage measurement and alternating current voltage measurement are selected, the microprocessor sends a control signal to a part of gear switching modules, gates the output voltage of the corresponding measurement module to the automatic range switching module, and the microprocessor sends an enabling signal to the automatic range switching module to enable the automatic range switching module to start working, the automatic range switching module automatically selects the range, the measuring range selection signal is returned to the microprocessor, the output signal of the measuring range automatic switching module is sent to the analog-digital conversion module, the analog-digital conversion module converts the analog voltage signal into a digital signal and sends the digital signal to the microprocessor, the microprocessor obtains a corresponding value to be measured according to the digital quantity and the measuring range selection signal, and if the selected working mode is capacitance measurement and inductance measurement, the measuring frequency is carried out in the microprocessor, so that the value of the element to be measured is obtained; and finally, printing the obtained result on an OLED display screen by the microprocessor, and displaying the final measurement result.
Although the present description uses terms such as resistance measuring module, dc voltage measuring module, ac voltage measuring module, capacitance measuring module, inductance measuring module, partial gear shifting module, automatic range shifting module, analog-to-digital conversion module, microprocessor, key module, display module, etc., more terms are used, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe the nature of the invention and they are to be construed as any additional limitation which is not in accordance with the spirit of the invention.
It should be understood that parts of the specification not set forth in detail are well within the prior art.
It should be understood that the above description of the preferred embodiments is given for clarity and not for any purpose of limitation, and that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. The utility model provides an intelligent multimeter of range automatic switch-over which characterized in that includes: the device comprises a resistance measuring module, a direct current voltage measuring module, an alternating current voltage measuring module, a capacitance measuring module, an inductance measuring module, a partial gear switching module, a range automatic switching module, an analog-to-digital conversion module, a microprocessor, a key module and a display module;
the partial gear switching module is respectively connected with the resistance measuring module, the direct-current voltage measuring module and the alternating-current voltage measuring module; the partial gear switching module, the range automatic switching module and the analog-to-digital conversion module are sequentially connected; the microprocessor is respectively connected with the partial gear switching module, the range automatic switching module, the analog-to-digital conversion module, the capacitance measuring module, the inductance measuring module, the key module and the display module.
2. The automatic range switching intelligent multimeter of claim 1 wherein: the resistance measuring module is used for detecting the size of the resistance, converting the resistance value into a voltage signal and outputting the voltage signal to the partial gear switching module.
3. The automatic range switching intelligent multimeter of claim 1 wherein: the direct-current voltage testing module is used for detecting the magnitude of a direct-current voltage signal and outputting a stable direct-current voltage signal to the partial gear switching module.
4. The automatic range switching intelligent multimeter of claim 1 wherein: the alternating voltage testing module is used for detecting the effective value of the alternating voltage signal and outputting a stable direct voltage signal to the partial gear switching module.
5. The automatic range switching intelligent multimeter of claim 1 wherein: the capacitance measuring module is used for detecting the size of the capacitance, the frequency of an output signal of the capacitance measuring module is only related to the resistance value of the circuit and the capacitance value to be detected, and the output signal is sent to the microprocessor.
6. The automatic range switching intelligent multimeter of claim 1 wherein: the inductance measuring module is used for detecting the size of the inductance, the frequency of an output signal of the module is only related to the capacitance value of the circuit and the inductance value to be detected, and the output signal is sent to the microprocessor.
7. The automatic range switching intelligent multimeter of claim 1 wherein: the partial gear control module is used for selecting one of the output voltage of the output resistance measuring module, the output voltage of the direct current voltage measuring module and the output voltage of the alternating current voltage measuring module according to control signals generated by selecting different measuring modes and sending the selected one to the automatic range switching module.
8. The automatic range switching intelligent multimeter of claim 1 wherein: the automatic range switching module is used for realizing automatic range switching, selecting a range suitable for an input signal and transmitting an output voltage of the module to the analog-to-digital conversion module, and the module is also used for outputting a range selection signal and transmitting the range selection signal to the microprocessor.
9. The automatic range switching intelligent multimeter of claim 1 wherein: the analog-to-digital conversion module is used for converting an input analog voltage signal into a digital signal and sending the digital signal to the microprocessor;
the microprocessor is used for controlling the working time sequence of the analog-to-digital conversion module and obtaining digital quantity from the analog-to-digital conversion module so as to obtain corresponding to-be-detected resistance, direct current voltage and alternating current voltage values; and the frequency measuring module is used for measuring the frequency of the signals output by the inductance measuring module and the capacitance measuring module so as to obtain the inductance value to be measured and the capacitance value to be measured.
10. The automatic range switching intelligent multimeter of claim 1 wherein: the key module is a 4-by-4 matrix keyboard and is used for selecting a measurement mode of the digital multimeter;
the display module is used for displaying the measured values in different measuring modes.
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| CN201920398039.1U CN209841947U (en) | 2019-03-25 | 2019-03-25 | Intelligent multimeter with automatic range switching function |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111175556A (en) * | 2020-01-19 | 2020-05-19 | 付涛阳 | Novel current transformer and implementation method |
| CN111736094A (en) * | 2020-07-23 | 2020-10-02 | 深圳市微特自动化设备有限公司 | PCI-E test card |
| CN111965407A (en) * | 2020-08-18 | 2020-11-20 | 中国南方电网有限责任公司超高压输电公司天生桥局 | Secondary circuit safety measuring equipment |
| CN112763079A (en) * | 2020-12-24 | 2021-05-07 | 中国科学院长春光学精密机械与物理研究所 | System and method for measuring focal plane temperature of satellite-borne infrared detector |
| WO2021253784A1 (en) * | 2020-06-16 | 2021-12-23 | 普源精电科技股份有限公司 | Multifunctional measurement device, resource configuration method, measurement method and apparatus, and medium |
-
2019
- 2019-03-25 CN CN201920398039.1U patent/CN209841947U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111175556A (en) * | 2020-01-19 | 2020-05-19 | 付涛阳 | Novel current transformer and implementation method |
| WO2021253784A1 (en) * | 2020-06-16 | 2021-12-23 | 普源精电科技股份有限公司 | Multifunctional measurement device, resource configuration method, measurement method and apparatus, and medium |
| CN111736094A (en) * | 2020-07-23 | 2020-10-02 | 深圳市微特自动化设备有限公司 | PCI-E test card |
| CN111736094B (en) * | 2020-07-23 | 2021-05-25 | 深圳市微特精密科技股份有限公司 | PCI-E test card |
| CN111965407A (en) * | 2020-08-18 | 2020-11-20 | 中国南方电网有限责任公司超高压输电公司天生桥局 | Secondary circuit safety measuring equipment |
| CN112763079A (en) * | 2020-12-24 | 2021-05-07 | 中国科学院长春光学精密机械与物理研究所 | System and method for measuring focal plane temperature of satellite-borne infrared detector |
| CN112763079B (en) * | 2020-12-24 | 2022-04-26 | 中国科学院长春光学精密机械与物理研究所 | System and method for measuring focal plane temperature of satellite-borne infrared detector |
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