High-precision solution conductivity measuring device

Abstract

The utility model relates to a high-precision solution conductivity measuring device, which comprises an electrode pen, a main control circuit and an impedance measuring circuit, the impedance measuring circuit comprises an amplifying circuit and an impedance measuring chip, the amplifying circuit is electrically connected with the electrode pen, and the output end of the amplifying circuit is connected with the impedance measuring chip. The output end of the impedance measuring chip is connected with the input end of the main control circuit, the input end of the main control circuit is further connected with a temperature sensor, the main control circuit is electrically connected with a communication module, and the main control circuit is in communication connection with an upper computer through the communication module; and the power supply circuit supplies power to the main control circuit, the impedance measurement circuit, the temperature sensor and the communication module. According to the utility model, the amplification circuit is arranged to amplify signals, the impedance measurement chip completes impedance detection, and finally, temperature compensation is combined, so that a hardware basis is provided for realizing high-precision solution conductivity detection.

Description

TECHNICAL FIELD

[0001] The utility model relates to solution conductivity measurement technical field, concretely relates to a high accuracy solution conductivity measuring device. BACKGROUND

[0002] Solution conductivity is an important physical quantity to describe the solution conductivity performance, and is widely used in environmental monitoring, food industry, chemical analysis and other fields. Although the common conductivity meter on the market has low price and can meet general measurement requirements, its measurement accuracy is limited, especially in high concentration or low concentration solution, the measurement error is large. For example, the error of the commercially available conductivity meter may exceed 5% when measuring high concentration solution, and even reach more than 20% in some cases. Such insufficient accuracy limits its use in scientific research and high-precision industrial applications.

[0003] Therefore, a high-precision solution conductivity detection device is needed. SUMMARY

[0004] The utility model discloses a kind of high-precision solution conductivity measuring devices to solve the problem of poor detection accuracy of existing conductivity meter. Amplification circuit is provided to amplify and process signal, then impedance detection is completed by impedance measurement chip, finally combined with temperature compensation, to provide hardware basis for realizing high-precision solution conductivity detection.

[0005] To achieve the above purpose, the utility model provides a kind of high-precision solution conductivity measuring device, including electrode pen, main control circuit and impedance measurement circuit, the impedance measurement circuit includes amplification circuit and impedance measurement chip, the amplification circuit is electrically connected electrode pen, the output end of amplification circuit is connected impedance measurement chip, the output end of impedance measurement chip is connected the input end of main control circuit, the input end of main control circuit is also connected with temperature sensor, main control circuit is electrically connected with communication module, main control circuit is communicated with host computer by communication module;

[0006] It further includes power supply circuit, and the power supply circuit supplies power for main control circuit, impedance measurement circuit, temperature sensor and communication module.

[0007] Further, the main control circuit includes STM32F103C8T6 chip, and the STM32F103C8T6 chip is provided with peripheral circuit.

[0008] The STM32F103C8T6 chip is electrically connected with USB interface.

[0009] The STM32F103C8T6 single-chip microcomputer circuit structure is simple and convenient for wiring, and high-precision data processing can be realized by combining algorithm. In addition, the chip cost is low, and it is convenient for promotion.

[0010] Further, the amplification circuit comprises an AD820ARMZ-RL chip, the impedance measurement chip comprises an AD5933 impedance converter, the AD5933 impedance converter is externally connected with a filter capacitor, a noise suppression inductor and a resistance for adjusting the output of the AD5933 impedance converter, and the electrode pen is connected between the output and input pins of the AD5933 impedance converter through the AD820ARMZ-RL chip.

[0011] The AD5933 impedance converter is connected with an STM32F103C8T6 chip through an I2C serial port.

[0012] The AD820ARMZ-RL chip amplifies the electrical signal collected by the electrode pen, and then the AD5933 impedance converter outputs the electrical signal to the STM32F103C8T6 chip to complete conductivity detection.

[0013] Further, the temperature sensor comprises a DS18B20 type temperature sensor, the DS18B20 type temperature sensor is provided with a probe, and the output end of the DS18B20 type temperature sensor is connected with an ADC pin of the STM32F103C8T6 chip.

[0014] The probe of the DS18B20 type temperature sensor is inserted into the detected solution and is used for sensing the temperature of the detected solution.

[0015] Further, the power supply circuit comprises a power supply, a power supply switch and a voltage stabilizing chip, the voltage stabilizing chip comprises an LTC1763CS8 chip, the LTC1763CS8 chip is connected with the power supply, the power supply switch is arranged on the LTC1763CS8 chip, and the power supply switch is used for controlling power-on and power-off.

[0016] The power supply switch is arranged as a manual switch, and power-on and power-off control of the equipment is realized.

[0017] Further, the communication module comprises an HC-05 Bluetooth module, and the HC-05 Bluetooth module is in communication with the STM32F103C8T6 chip through a UART serial port.

[0018] Further, the electrode pen comprises a platinum black electrode, the platinum black electrode is adopted, the polarization effect is reduced, and the measurement precision is further improved.

[0019] Through the above technical scheme, the utility model has the beneficial effects that:

[0020] The utility model discloses a high-precision solution conductivity measuring device, including electrode pen 1, main control circuit 2 and impedance measurement circuit, impedance measurement circuit includes amplifier circuit 3 and impedance measurement chip 4, amplifier circuit 3 is electrically connected electrode pen 1, and the output of amplifier circuit 3 is connected impedance measurement chip 4, and the output of impedance measurement chip 4 is connected the input of main control circuit 2, and the input of main control circuit 2 is also connected with temperature sensor 5, and main control circuit 2 is electrically connected with communication module 6, and main control circuit 2 is connected with host computer 7 through communication module 6, BRIEF DESCRIPTION OF DRAWINGS

[0021] Fig. 1 It is one of circuit diagram of the utility model high-precision solution conductivity measuring device.

[0022] Fig. 2 It is two of circuit diagram of the utility model high-precision solution conductivity measuring device.

[0023] Fig. 3 It is three of circuit diagram of the utility model high-precision solution conductivity measuring device.

[0024] Figure reference: electrode pen 1, main control circuit 2, amplifier circuit 3, impedance measurement chip 4, temperature sensor 5, communication module 6, host computer 7, power switch 8, voltage stabilizing chip 9. DETAILED DESCRIPTION

[0025] Example 1

[0026] As Figs. 1-3 Shown, a kind of high-precision solution conductivity measuring device, including electrode pen 1, main control circuit 2 and impedance measurement circuit, impedance measurement circuit includes amplifier circuit 3 and impedance measurement chip 4, amplifier circuit 3 is electrically connected electrode pen 1, and the output of amplifier circuit 3 is connected impedance measurement chip 4, and the output of impedance measurement chip 4 is connected the input of main control circuit 2, and the input of main control circuit 2 is also connected with temperature sensor 5, and main control circuit 2 is electrically connected with communication module 6, and main control circuit 2 is connected with host computer 7 through communication module 6;

[0027] It further includes power supply circuit, and the power supply circuit is powered for main control circuit 2, impedance measurement circuit, temperature sensor 5 and communication module 6.

[0028] The main control circuit 2 includes STM32F103C8T6 chip, and the STM32F103C8T6 chip is provided with peripheral circuit;

[0029] STM32F103C8T6 chip is electrically connected with USB interface.

[0030] The amplification circuit 3 comprises an AD820ARMZ-RL chip, the impedance measurement chip 4 comprises an AD5933 impedance converter, the AD5933 impedance converter is externally connected with a filter capacitor, a noise suppression inductor and a resistance for adjusting the output of the AD5933 impedance converter, the electrode pen 1 is connected between the output and input pins of the AD5933 impedance converter through the AD820ARMZ-RL chip.

[0031] The AD5933 impedance converter is connected with an STM32F103C8T6 chip through an I2C serial port.

[0032] The temperature sensor 5 comprises a DS18B20 temperature sensor, the DS18B20 temperature sensor is provided with a probe, and the output end of the DS18B20 temperature sensor is connected with an ADC pin of the STM32F103C8T6 chip.

[0033] The power supply circuit comprises a power supply, a power switch 8 and a voltage stabilizing chip 9, the voltage stabilizing chip 9 comprises an LTC1763CS8 chip, the LTC1763CS8 chip is connected with the power supply, the LTC1763CS8 chip is provided with the power switch 8, and the power switch 8 is used for controlling power on and off.

[0034] The communication module 6 comprises an HC-05 Bluetooth module, and the HC-05 Bluetooth module communicates with the STM32F103C8T6 chip through a UART serial port.

[0035] The electrode pen 1 comprises a platinum black electrode.

[0036] When working, the power switch 8 is turned on, the electrical equipment is powered on, the probe of the DS18B20 temperature sensor is inserted into the solution, then the electrode pen 1 is placed into the solution, the loop between the amplification circuit 3 and the impedance measurement chip 4 of the electrode pen 1 is connected, the AD5933 impedance converter converts the solution impedance into an electrical signal, the electrical signal is received by the STM32F103C8T6 chip, and the STM32F103C8T6 chip obtains the solution conductivity in combination with the detection signal of the DS18B20 temperature sensor. The STM32F103C8T6 chip sends the detection parameters to the host computer through the HC-05 Bluetooth module.

[0037] Through experiments, the measurement error of the device is less than 2.8% in the concentration range of 0.001-3 mol / L.

[0038] Embodiment 2

[0039] Based on the device in the embodiment and the computer program, the application has the following functions.

[0040] 1After the solution conductivity is obtained, the STM32F103C8T6 chip calculates the TDS value of the water quality through the linear relationship between the conductivity and the total dissolved solids (TDS), so as to realize the measurement of the water quality.

[0041] 2According to the functional relationship between the conductivity and the salt solution concentration, the concentration of the salt solution is calculated.

[0042] 3The double-layer capacitance in the solution is determined through the impedance measurement under the low-frequency excitation signal.

[0043] The above-mentioned embodiments are only preferred embodiments of the present application, and are not intended to limit the scope of the present application. Therefore, equivalent changes or modifications made to the structure, features and principles described in the patent range of the present application should be included in the patent range of the present application.

Claims

1. A high-precision solution conductivity measuring device comprising an electrode pen (1), a main control circuit (2) and an impedance measuring circuit, characterized in that, The impedance measurement circuit comprises an amplification circuit (3) and an impedance measurement chip (4), the amplification circuit (3) is electrically connected with the electrode pen (1), the output end of the amplification circuit (3) is connected with the impedance measurement chip (4), the output end of the impedance measurement chip (4) is connected with the input end of the master control circuit (2), the input end of the master control circuit (2) is also connected with a temperature sensor (5), the master control circuit (2) is electrically connected with a communication module (6), and the master control circuit (2) is in communication connection with a host computer (7) through the communication module (6); The power supply circuit supplies power for the master control circuit (2), the impedance measurement circuit, the temperature sensor (5) and the communication module (6).

2. The high-precision solution conductivity measuring device according to claim 1, characterized in that, The master control circuit (2) comprises an STM32F103C8T6 chip, and the STM32F103C8T6 chip is provided with a peripheral circuit. The STM32F103C8T6 chip is electrically connected with a USB interface.

3. The high-precision solution conductivity measuring device according to claim 2, characterized in that The amplification circuit (3) comprises an AD820ARMZ-RL chip, the impedance measurement chip (4) comprises an AD5933 impedance converter, the AD5933 impedance converter is peripherally connected with a filter capacitor, a noise suppression inductor and a resistor for adjusting the output of the AD5933 impedance converter, and the electrode pen (1) is connected between the output and input pins of the AD5933 impedance converter through the AD820ARMZ-RL chip; The AD5933 impedance converter is connected with the STM32F103C8T6 chip through an I2C serial port.

4. The high-precision solution conductivity measuring device according to claim 2, characterized in that, The temperature sensor (5) comprises a DS18B20 temperature sensor, the DS18B20 temperature sensor is provided with a probe, and the output end of the DS18B20 temperature sensor is connected with the ADC pin of the STM32F103C8T6 chip.

5. The high-precision solution conductivity measuring device according to claim 1, characterized in that, The power supply circuit comprises a power supply, a power switch (8) and a voltage stabilizing chip (9), the voltage stabilizing chip (9) comprises an LTC1763CS8 chip, the LTC1763CS8 chip is connected with the power supply, the LTC1763CS8 chip is provided with the power switch (8), and the power switch (8) is used for controlling the on-off of power supply.

6. The high-precision solution conductivity measuring device according to claim 2, characterized in that, The communication module (6) comprises an HC-05 Bluetooth module, and the HC-05 Bluetooth module communicates with the STM32F103C8T6 chip through a UART serial port.

7. The high-precision solution conductivity measuring device according to claim 1, characterized in that, The electrode pen (1) comprises a platinum black electrode.

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