Full-isolation high-synchronization electrochemical signal acquisition method, circuit and electrochemical workstation

Abstract

The invention provides a full-isolation high-synchronization electrochemical signal acquisition method and circuit and an electrochemical workstation, and the method comprises the steps: sending a digital request signal through a microprocessor, transmitting the request signal to a magnetic coupler through an FPGA (Field Programmable Gate Array), and further transmitting the signal to a DAC (Digital-to-Analog Converter) and an ADC (Analog-to-Digital Converter) through the magnetic coupler. The DAC generates an electrochemical excitation signal through the electrochemical preceding stage, excites the electrolytic tank to generate a Faraday current, and converts the Faraday current into a voltage signal through transconductance. The ADC collects the voltage signal and stores the voltage signal in a register. The microprocessor sends a measurement request through the FPGA, data of the ADC is transmitted back to the FPGA through the magnetic coupler and finally transmitted to the microprocessor at a time, and high-synchronization electrochemical signal collection is achieved. The method has the advantages of full-isolation design, high synchronism and high precision, interference can be effectively reduced, the reliability and precision of electrochemical signal acquisition are improved, and the method is widely applied to the fields of electrochemical research, environmental monitoring, biosensing and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of electrochemical industry signal detection, and in particular to a fully isolated high-synchronous electrochemical signal acquisition method, a circuit and an electrochemical workstation. Background Art

[0002] When conducting a multi-electrolytic cell system, we generally use a multi-channel electrochemical workstation for measurement. The measuring components of the existing electrochemical workstation will have more or less electrical coupling. In particular, the ground coupling between each unit module means that in the unit module, we have a reference potential related to the electrochemical detector, but sometimes the potential of our electrolytic cell itself is floating, and multiple electrolytic cells need to be measured simultaneously and independently. For example, some biological-related electrochemical tests, especially those that are both connected and independent of each other, also require strict time and simultaneous measurement of electrochemical tests. Therefore, it is somewhat difficult to use a general multi-channel electrochemical workstation. For example, when conducting biological tests, the organism itself has its own potential, and there is also a potential difference between different parts of the organism. These biological reference electrical signals may be important parameters for the work of the organism. After coupling at the electrochemical workstation end, the electrochemical workstation end will affect the potential of the organism itself and pull it to the vicinity of the reference potential of the electrochemical workstation. Therefore, it may affect the operation of the organism itself and cause deviations in the experimental results. Secondly, the electrochemical workstation based on microprocessor may be affected by the sequential execution of the program, that is, the measurement request of system 1 is sent first, and then the measurement request of system 2. In interconnected electrochemical cells such as different parts of a biological body, we sometimes need to strictly measure the changes in microcurrents at different locations at the same time. Therefore, multi-channel acquisition using a microprocessor-based electrochemical workstation has its limitations. Summary of the invention

[0003] In view of the above problems, the present invention innovatively proposes a fully isolated high-synchronous electrochemical signal acquisition method, circuit and electrochemical workstation, which achieves complete electrical decoupling of the three-electrode electrolytic cell system through the isolation of digital signals by flyback switching power supply and magnetic coupler. Each electrolytic cell measurement electrode group floats with the reference potential of the electrolytic cell system itself, without affecting the potential difference measurement in the electrode and the Faraday current measurement. The influence of the measuring tool on the measuring body is minimized.

[0004] Specifically, the fully isolated high-synchronous electrochemical signal acquisition method described in the present invention at least includes:

[0005] S1: The microprocessor sends a digital request signal to the FPGA, and the FPGA sends the corresponding request to the corresponding magnetic coupler at the same time;

[0006] S2: The magnetic coupler sends the digital request signal to the corresponding DAC and ADC simultaneously;

[0007] S3: DAC transmits the digital request signal to the electrolytic cell through the electrochemical front stage to form an electrochemical excitation signal;

[0008] S4: The Faraday current stimulated by the electrochemical excitation signal passes through the working electrode of the electrolytic cell and then converts the current into a voltage through transconductance. The ADC collects the voltage signal and stores it in a register inside the ADC.

[0009] S5: The microprocessor sends a measurement request from the ADC to the FPGA. The FPGA sends the measurement request to the magnetic coupler. The magnetic coupler sends the measurement request to the ADC. The data in the ADC register is sent back to the FPGA through the magnetic coupler. The FPGA uses an array to store the data returned by multiple ADCs and sends it to the microprocessor at one time to complete synchronous acquisition.

[0010] Before step S1, the following steps are also included:

[0011] The external power supply is input to the primary side of the flyback switching power supply. The flyback switching power supply outputs the power signal on the feedback side through the magnetic field winding and the iron core, and uses the power chip for voltage regulation. At the same time, the feedback side of the flyback switching power supply supplies power to the microprocessor and FPGA.

[0012] The microprocessor and the FPGA, as well as the FPGA and the DAC or ADC, are connected via an I2C or SPI bus.

[0013] The DAC and ADC correspond to the magnetic couplers one by one; each magnetic coupler operates independently, and the voltage difference of each magnetic coupler is the same or different;

[0014] There is at least one electrolytic cell.

[0015] As another preferred embodiment, the present invention further provides a fully isolated high-synchronous electrochemical signal acquisition circuit, the circuit comprising: a power supply circuit, a magnetic coupler, a control module, a feedback side of a flyback switching power supply, a plurality of flyback switching power supply secondary sides, a digital-to-analog conversion module, an electrochemical front stage, a transconductance system and an electrolytic cell; the digital-to-analog conversion module comprises a DAC and an ADC; the power supply circuit comprises a power supply chip and a flyback switching power supply primary side;

[0016] The primary side of the flyback switching power supply is connected to an external power supply and is stabilized by the voltage stabilizing circuit; the stabilized voltage is sent to the secondary sides of the plurality of flyback switching power supplies via a magnetic coupler; the magnetic coupler is connected to a control module;

[0017] The secondary side of the flyback switching power supply is connected to a digital-to-analog conversion module, and the digital-to-analog conversion module is connected to an electrolytic cell through an electrochemical front stage and a transconductance system.

[0018] The power chip and the primary side of the flyback switching power supply also include:

[0019] The REF pin and VCC pin of the power chip are respectively connected to capacitors C27 and C30 and then connected to the DGND terminal; the COMP pin is connected to resistor R51, and the resistor R51 is connected in parallel with capacitor C25; the FB pin is connected to resistor R53 and connected to the power supply; the resistor R54 is connected in parallel with resistor R53 and grounded; the CS pin is connected to capacitor C31 and then grounded; the RC pin is connected to capacitor C31 and then grounded; the OUT pin is connected to the input end of the magnetic coupler through a protection circuit as the primary side of the flyback switching power supply; the input end of the magnetic coupler is also connected in parallel with capacitors C21, C22, C23 and C24; the input end of the magnetic coupler is connected to the low-side gate LG and the input end IG.

[0020] The protection circuit includes a resistor R48 and a diode D20 connected in parallel with the resistor R48.

[0021] The control module includes: a microprocessor and an FPGA; the microprocessor and the FPGA are powered by the feedback side of a flyback switching power supply; the microprocessor is used to send a digital request signal to the FPGA, and the FPGA simultaneously sends the corresponding request to the corresponding magnetic coupler.

[0022] As another preferred embodiment, the present invention further provides an electrochemical workstation, wherein the electrochemical workstation adopts the fully isolated high-synchronous electrochemical signal acquisition circuit as described above.

[0023] In summary, the present invention proposes a fully isolated high-synchronous electrochemical signal acquisition method, circuit and electrochemical workstation, in which each part is electrically isolated by a magnetic coupler, thereby avoiding interference between signals and enhancing the reliability of the system. Through the coordinated control of FPGA and microprocessor, the time synchronization in the signal acquisition process is ensured, and the accuracy and consistency of the data are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the fully isolated and highly synchronized electrochemical signal acquisition method of the present invention.

[0025] Figure 2 This is a basic configuration diagram of the fully isolated high-synchronous electrochemical signal acquisition circuit described in the present invention.

[0026] Figure 3 This is another fully isolated high-synchronous electrochemical signal acquisition circuit diagram described in the present invention. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1, as Figure 1 As shown, a fully isolated high-synchronous electrochemical signal acquisition method at least includes:

[0029] S1: The microprocessor sends a digital request signal to the FPGA, and the FPGA sends the corresponding request to the corresponding magnetic coupler at the same time;

[0030] Among them, the microprocessor, preferably ARM, DSP, etc., acts as the control core in the whole system, responsible for initiating acquisition requests, configuring the system and processing data. It is usually connected to FPGA and sends digital request signals through standard communication protocols such as SPI, I2C or direct GPIO control. FPGA (field programmable gate array) acts as the core of data processing and synchronization control. It is responsible for receiving the request signal of the microprocessor, generating appropriate control signals, and transmitting the request to multiple components at the same time, such as magnetic couplers, DACs and ADCs, to ensure the synchronization and real-time performance of the acquisition process.

[0031] S2: The magnetic coupler sends the digital request signal to the corresponding DAC and ADC at the same time; wherein the magnetic coupler is the electrical isolation layer of the system, which is usually used to eliminate ground noise between different circuits. The magnetic coupler transmits the signal wirelessly, thereby avoiding interference caused by the electrical ground loop.

[0032] S3: DAC transmits the digital request signal to the electrolytic cell through the electrochemical front stage to form an electrochemical excitation signal;

[0033] Among them, the electrochemical pre-stage circuit is used to convert the signal output by the DAC into a suitable electrochemical excitation signal. This process usually involves steps such as amplification, filtering, and impedance matching to ensure that the electrical signal can effectively stimulate the electrochemical reaction in the electrolytic cell.

[0034] The electrolyte and electrodes in the electrolytic cell together form the environment for electrochemical reactions. The electrochemical excitation signal generated by the DAC will pass through the working electrode of the electrolytic cell, which is usually a metal or carbon-based material, and apply an external voltage to stimulate the redox reaction of the electrolyte in the electrolytic cell, thereby generating a Faraday current.

[0035] S4: The Faraday current stimulated by the electrochemical excitation signal passes through the working electrode of the electrolytic cell and then converts the current into a voltage through transconductance. The ADC collects the voltage signal and stores it in a register inside the ADC.

[0036] The current generated by the electrochemical reaction in the electrolytic cell is usually proportional to the concentration change of the substance in the electrode reaction. This current is weak and needs to be converted through a transconductance amplifier, preferably a transconductance amplifier, from a current signal to a voltage signal to facilitate subsequent collection and processing.

[0037] Preferably, in order to improve the accuracy of the signal, the resolution of the ADC is usually higher, such as 16 bits or 24 bits, so as to accurately measure weak voltage changes. The registers inside the ADC are used to store these collected data and prepare to extract them through subsequent requests.

[0038] S5: The microprocessor sends the ADC measurement request to the FPGA, the FPGA sends the measurement request to the magnetic coupler, the magnetic coupler sends the measurement request to the ADC, the data in the ADC register is sent back to the FPGA through the magnetic coupler, the FPGA uses an array to store the data returned by multiple ADCs, and sends it to the microprocessor at one time to complete the synchronous acquisition. Furthermore, the microprocessor can perform further calculations, filtering, signal analysis and other operations based on the collected data, and finally obtain the required electrochemical signal analysis results.

[0039] Preferably, the FPGA is responsible for storing the data returned by multiple ADCs in an array or cache. These data storages are usually FIFO first-in first-out buffers or memory blocks, which can ensure the order and synchronization of data. The FPGA controls the transmission rate and order of data to ensure that multiple signal channels, such as multiple ADC channels, can work simultaneously and collect synchronously.

[0040] Through the above scheme, the electrical isolation in the system is achieved through the magnetic coupler, which can effectively avoid electrical noise interference between different parts of the system, improve the accuracy of the signal and the stability of the system. Through high-precision DAC and ADC, transconductance amplifier and other components, this method can perform high-precision electrochemical signal acquisition, which is suitable for applications that require accurate measurement of electrochemical reactions or the working status of electrolytic cells. By controlling the parallel acquisition and transmission of multiple channel data through FPGA, data from multiple signal sources can be processed simultaneously, greatly improving the acquisition efficiency.

[0041] Preferably, before step S1, the method further includes: an external power supply is input into the primary side of the flyback switching power supply, the flyback switching power supply outputs a power supply signal on the feedback side through the magnetic field winding and the iron core, and uses a power chip to stabilize the voltage, and at the same time, the feedback side of the flyback switching power supply supplies power to the microprocessor and the FPGA.

[0042] Among them, the basic structure of the flyback switching power supply is:

[0043] Primary side: The primary side of a flyback switching power supply usually includes a switch tube (such as MOSFET, IGBT, etc.), a field winding (transformer) and a control circuit. The input power signal is modulated by the switch tube, and a high-frequency and high-voltage pulse signal is generated under the action of the transformer's magnetic field.

[0044] Field winding and core: The transformer of the flyback switching power supply consists of an iron core and a field winding. The iron core provides the magnetic flux path, and the winding is responsible for generating the electromagnetic induction effect. Through high-frequency switching operation, the transformer of the flyback power supply can effectively convert the voltage of the input power supply to the required lower voltage, and also has an electrical isolation function to avoid ground loop problems inside the system.

[0045] Preferably, the core function of the voltage stabilizing chip is to adjust the switching frequency or the on-time of the switch according to the feedback signal to keep the output voltage stable.

[0046] Preferably, the output side of the flyback switching power supply will supply the stabilized power to the microprocessor (MCU) and FPGA through a power distribution circuit (such as an LDO regulator or a DC-DC converter). Different modules may require different voltages. The voltage output by the flyback switching power supply is first adjusted to an appropriate voltage, such as 3.3V, 5V or 1.8V, by a voltage regulator, and then supplied to the microprocessor and FPGA.

[0047] The microprocessor and the FPGA, as well as the FPGA and the DAC or ADC, are connected via an I2C or SPI bus.

[0048] The DAC and ADC correspond to the magnetic couplers one by one; each magnetic coupler operates independently, and the voltage difference of each magnetic coupler is the same or different;

[0049] There is at least one electrolytic cell.

[0050] Embodiment 2, as Figure 2-3 As shown, the present invention also provides a fully isolated high-synchronous electrochemical signal acquisition circuit, the circuit comprising: a power supply circuit, a magnetic coupler, a control module, a feedback side of a flyback switching power supply, a plurality of flyback switching power supply secondary sides, a digital-to-analog conversion module, an electrochemical front stage, a transconductance system and an electrolytic cell; the digital-to-analog conversion module comprises a DAC and an ADC; the power supply circuit comprises a power supply chip and a flyback switching power supply primary side;

[0051] Among them, the magnetic coupler is responsible for transmitting the voltage stabilized by the primary side of the flyback switching power supply to the secondary side through electromagnetic induction. The magnetic coupler ensures the electrical isolation of the power supply system, avoids the interference of the ground loop, and also provides the necessary power isolation to improve the anti-interference ability and safety of the system.

[0052] The electrochemical pre-stage is responsible for amplifying the signal from the electrolytic cell and passing it to the transconductance system. Its focus is on amplifying and filtering weak electrochemical signals to ensure signal quality.

[0053] The electrolytic cell is the core part of the entire electrochemical signal acquisition system and is used for electrochemical reactions. The state and behavior of the electrolytic cell directly affect the acquisition and analysis of the signal, and the transconductance system helps control the working state of the electrolytic cell.

[0054] The primary side of the flyback switching power supply is connected to an external power supply and is stabilized by the voltage stabilizing circuit; the stabilized voltage is sent to the secondary sides of the plurality of flyback switching power supplies via a magnetic coupler; the magnetic coupler is connected to a control module;

[0055] The secondary side of the flyback switching power supply is connected to a digital-to-analog conversion module, and the digital-to-analog conversion module is connected to an electrolytic cell through an electrochemical front stage and a transconductance system.

[0056] This application achieves full isolation through a flyback switching power supply and a magnetic coupler, avoiding ground loop problems and signal noise interference. This design effectively improves the system's anti-interference ability, especially in the application scenario of high-precision electrochemical signal acquisition, and can provide higher stability and signal quality.

[0057] The power chip and the primary side of the flyback switching power supply also include:

[0058] The REF pin and VCC pin of the power chip are respectively connected to capacitors C27 and C30 and then connected to the DGND terminal; the COMP pin is connected to resistor R51, and the resistor R51 is connected in parallel with capacitor C25; the FB pin is connected to resistor R53 and connected to the power supply; the resistor R54 is connected in parallel with resistor R53 and grounded; the CS pin is connected to capacitor C31 and then grounded; the RC pin is connected to capacitor C31 and then grounded; the OUT pin is connected to the input end of the magnetic coupler through a protection circuit as the primary side of the flyback switching power supply; the input end of the magnetic coupler is also connected in parallel with capacitors C21, C22, C23 and C24; the input end of the magnetic coupler is connected to the low-side gate LG and the input end IG.

[0059] The protection circuit includes a resistor R48 and a diode D20 connected in parallel with the resistor R48.

[0060] The control module includes: a microprocessor and an FPGA; the microprocessor and the FPGA are powered by the feedback side of a flyback switching power supply; the microprocessor is used to send a digital request signal to the FPGA, and the FPGA simultaneously sends the corresponding request to the corresponding magnetic coupler.

[0061] Embodiment 3: The present invention further provides an electrochemical workstation, wherein the electrochemical workstation adopts the fully isolated high-synchronous electrochemical signal acquisition circuit as described in the above embodiment 2.

[0062] The electrochemical workstation described in the present application adopts a fully isolated high-synchronous electrochemical signal acquisition circuit to ensure high precision and synchronization during the signal acquisition process. This feature is crucial for the accurate measurement of tiny currents and voltages in electrochemical experiments. Since the electrochemical signal acquisition circuit adopts a fully isolated design of a flyback switching power supply, the workstation can effectively avoid ground loop noise interference, thereby improving signal quality and enhancing the system's anti-interference ability. This workstation supports the synchronous acquisition and processing of multiple electrochemical signal channels, and can monitor multiple electrolytic cells or electrochemical reaction processes at the same time. This multi-channel synchronous acquisition capability is very suitable for the needs of a variety of electrochemical analyses and experiments, such as detecting electrochemical signals of multiple sensors or multiple experimental points at the same time.

[0063] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A fully isolated high-synchronous electrochemical signal acquisition method, characterized in that: The method comprises: S1: The microprocessor sends a digital request signal to the FPGA, and the FPGA sends the corresponding request to the corresponding magnetic coupler at the same time; S2: The magnetic coupler sends the digital request signal to the corresponding DAC and ADC simultaneously; S3: DAC transmits the digital request signal to the electrolytic cell through the electrochemical front stage to form an electrochemical excitation signal; S4: The Faraday current stimulated by the electrochemical excitation signal passes through the working electrode of the electrolytic cell and then converts the current into a voltage through transconductance. The ADC collects the voltage signal and stores it in a register inside the ADC. S5: The microprocessor sends a measurement request from the ADC to the FPGA. The FPGA sends the measurement request to the magnetic coupler. The magnetic coupler sends the measurement request to the ADC. The data in the ADC register is sent back to the FPGA through the magnetic coupler. The FPGA uses an array to store the data returned by multiple ADCs and sends it to the microprocessor at one time to complete synchronous acquisition.

2. A fully isolated high-synchronous electrochemical signal acquisition method according to claim 1, characterized in that: Before step S1, the following steps are also included: The external power supply is input to the primary side of the flyback switching power supply. The flyback switching power supply outputs the power signal on the feedback side through the magnetic field winding and the iron core, and uses the power chip for voltage regulation. At the same time, the feedback side of the flyback switching power supply supplies power to the microprocessor and FPGA.

3. A fully isolated high-synchronous electrochemical signal acquisition method according to claim 2, characterized in that: The microprocessor and the FPGA, as well as the FPGA and the DAC or ADC, are connected via an I2C or SPI bus.

4. A fully isolated high-synchronous electrochemical signal acquisition method according to claim 3, characterized in that: The DAC and ADC correspond to the magnetic couplers one by one; each magnetic coupler operates independently, and the voltage difference of each magnetic coupler is the same or different; There is at least one electrolytic cell.

5. A fully isolated high-synchronous electrochemical signal acquisition circuit, characterized in that: The circuit includes: a power supply circuit, a magnetic coupler, a control module, a feedback side of a flyback switching power supply, a plurality of secondary sides of flyback switching power supplies, a digital-to-analog conversion module, an electrochemical front stage, a transconductance system and an electrolytic cell; the digital-to-analog conversion module includes a DAC and an ADC; the power supply circuit includes a power supply chip and a primary side of a flyback switching power supply; The primary side of the flyback switching power supply is connected to an external power supply and is stabilized by the voltage stabilizing circuit; the stabilized voltage is sent to the secondary sides of the plurality of flyback switching power supplies via a magnetic coupler; the magnetic coupler is connected to a control module; The secondary side of the flyback switching power supply is connected to a digital-to-analog conversion module, and the digital-to-analog conversion module is connected to an electrolytic cell through an electrochemical front stage and a transconductance system.

6. The circuit according to claim 5, characterized in that The power chip and the primary side of the flyback switching power supply also include: The REF pin and VCC pin of the power chip are respectively connected to capacitors C27 and C30 and then connected to the DGND terminal; the COMP pin is connected to resistor R51, and the resistor R51 is connected in parallel with capacitor C25; the FB pin is connected to resistor R53 and connected to the power supply; the resistor R54 is connected in parallel with resistor R53 and grounded; the CS pin is connected to capacitor C31 and then grounded; the RC pin is connected to capacitor C31 and then grounded; the OUT pin is connected to the input end of the magnetic coupler through a protection circuit as the primary side of the flyback switching power supply; the input end of the magnetic coupler is also connected in parallel with capacitors C21, C22, C23 and C24; the input end of the magnetic coupler is connected to the low-side gate LG and the input end IG.

7. The circuit according to claim 6, characterized in that The protection circuit includes a resistor R48 and a diode D20 connected in parallel with the resistor R48.

8. The circuit according to claim 7, characterized in that The control module includes: a microprocessor and an FPGA; the microprocessor and the FPGA are powered by the feedback side of a flyback switching power supply; the microprocessor is used to send a digital request signal to the FPGA, and the FPGA simultaneously sends the corresponding request to the corresponding magnetic coupler.

9. An electrochemical workstation, characterized in that: A fully isolated high-synchronous electrochemical signal acquisition circuit as described in any one of claims 5 to 8 is used.

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