Low-delay droplet driving information feedback sensing circuit

Abstract

The invention relates to a liquid drop driving information feedback sensing circuit and a detection method, belongs to the technical field of micro-fluidic chips, and solves the problems of low accuracy and poor real-time performance of liquid drop driving information feedback in the prior art. The liquid drop driving information feedback sensing circuit comprises a tested micro-fluidic chip, a voltage dividing element, a driving power supply and a voltage dividing acquisition circuit, the tested micro-fluidic chip, the voltage dividing element and the driving power supply are connected in series to form a loop, and the voltage dividing acquisition circuit comprises an acquisition module and a plurality of first amplification channels arranged in parallel. Each first amplification channel comprises a first amplifier and a first AC-to-DC element which are connected in series, and the amplification coefficients of the first amplifiers of the first amplification channels are different. According to the invention, real-time acquisition of the voltage signal in the droplet driving process is realized, the signal reading speed and accuracy are ensured, and the accuracy of the fed-back droplet driving information is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of microfluidic chips, and in particular to a droplet drive information feedback sensing circuit and a detection method. Background Art

[0002] In the application of biological reaction processes in microfluidic chips, different types of droplets in the chip need to complete multiple movement and reaction functions such as migration, fusion, and splitting. Therefore, the source of power for droplet movement, that is, the drive control of the droplets and the feedback of the movement position information during the drive process, are important links in the realization of the functions of the chip and even the microfluidic equipment. Real-time monitoring and feedback of the droplet movement state can enable the equipment operator to judge the working state of the microfluidic chip, whether the droplets move normally according to the planned movement path, and whether the droplet movement position is correct, so that when abnormal droplet movement occurs in the chip, the cause can be promptly investigated and adjustment measures can be taken.

[0003] At present, most of the real-time monitoring schemes for the motion state of droplets in microfluidic chips use the capacitance value collected by the capacitance detection circuit to determine the position of the droplets. Among them, some hardware circuits use timers to time-share the voltage drive circuit and the capacitance detection circuit. The voltage drive circuit and the capacitance detection circuit cannot work at the same time. When performing capacitance detection, the drive control of the droplet needs to be stopped, which takes up a lot of time and resources. In addition, the existing capacitance detection circuit has problems such as large interference and slow detection speed.

[0004] Since changes in capacitance will cause changes in the corresponding voltage signal, the existing technology also monitors the motion state of the droplet through a voltage acquisition circuit. For example, in the existing droplet drive information feedback sensor circuit, a method (point drawing method) is adopted to read the drive voltage signal value point by point and then superimpose it to form a feedback curve. However, this method has problems such as inaccurate sampling data and abnormal individual data points leading to inaccurate overall feedback information. That is, the data sampling frequency needs to meet certain requirements and abnormal signal points need to be shielded. At the same time, for the voltage signal changes caused by capacitance changes, the existing acquisition method uses the switching of the range to ensure that signals of different sizes can be accurately identified. However, the long range switching time of this method causes the range switching during the droplet movement to fail to keep up with the change of the equivalent capacitance, which will cause delays in the acquisition of voltage signal data and feedback of erroneous information. Summary of the invention

[0005] In view of the above analysis, the embodiments of the present invention aim to provide a droplet driving information feedback sensing circuit and detection method, so as to solve the problems of low accuracy and poor real-time performance of droplet driving information feedback in the prior art.

[0006] On the one hand, an embodiment of the present invention provides a droplet drive information feedback sensing circuit, the droplet drive information feedback sensing circuit comprising: a microfluidic chip to be tested, a voltage divider element, a driving power supply and a voltage divider acquisition circuit,

[0007] The microfluidic chip under test, the voltage divider element and the driving power supply are connected in series to form a loop,

[0008] The voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, each of the first amplifying channels includes a first amplifier and a first AC-DC converter connected in series, and the amplification factor of the first amplifier of each first amplifying channel is different.

[0009] The acquisition module is used to acquire the voltage division signal at both ends of the voltage division element, the first amplifier is used to amplify the acquired voltage division signal, and the first AC-DC conversion element is used to convert the voltage division signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage division signal measurement value.

[0010] The current equivalent capacitance value of the microfluidic chip under test is calculated according to the collected measured value of the voltage division signal and the effective value of the driving voltage signal applied by the driving power supply to obtain the movement position information of the droplet.

[0011] Based on the further improvement of the above-mentioned droplet drive information feedback sensing circuit, the first AC-DC converter is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

[0012] Based on the further improvement of the above droplet driving information feedback sensing circuit, the voltage dividing element includes a voltage dividing resistor or a voltage dividing capacitor.

[0013] Based on the further improvement of the above droplet driving information feedback sensing circuit, the voltage division acquisition circuit further includes: a first voltage follower,

[0014] The first voltage follower is connected between the output end of the acquisition module and the input ends of the plurality of first amplification channels.

[0015] Based on the further improvement of the above droplet drive information feedback sensing circuit, the droplet drive information feedback sensing circuit further includes: a processing module,

[0016] The processing module is respectively connected to the output ends of the plurality of first amplification channels. The processing module selects a voltage division signal measurement value output by one of the first amplification channels as a valid measurement value according to a preset threshold value, which is used to calculate the current equivalent capacitance value of the microfluidic chip under test to obtain the movement position information of the droplet.

[0017] Based on the further improvement of the above droplet driving information feedback sensing circuit, the droplet driving information feedback sensing circuit further includes: a driving voltage acquisition circuit,

[0018] The driving voltage acquisition circuit includes: an attenuation module, a second amplifier and a second AC-DC conversion element,

[0019] The attenuation module is used to collect and attenuate the driving voltage signal applied by the driving power supply, the second amplifier is used to amplify the attenuated driving voltage signal, and the second AC-DC element is used to convert the amplified driving voltage signal from an AC signal to a DC signal and output it as a driving voltage signal measurement value;

[0020] Wherein, the effective value of the driving voltage signal is calculated according to the measured value of the driving voltage signal.

[0021] Based on the further improvement of the above droplet driving information feedback sensing circuit, the driving voltage acquisition circuit further includes: a second voltage follower,

[0022] The second voltage follower is connected between the output terminal of the attenuation module and the input terminal of the second amplifier.

[0023] On the other hand, an embodiment of the present invention provides a method for detecting droplet driving information, which is implemented based on the droplet driving information feedback sensing circuit as described above, and the method includes:

[0024] Acquire measurement values ​​of a plurality of divided voltage signals respectively through a plurality of first amplification channels of the divided voltage acquisition circuit;

[0025] Selecting a voltage division signal measurement value output by one of the first amplification channels as a valid measurement value according to a preset threshold;

[0026] Acquire the effective value of the driving voltage signal applied by the driving power supply;

[0027] The current equivalent capacitance value of the measured microfluidic chip is calculated according to the selected voltage division signal measurement value and the driving voltage signal measurement value to obtain the movement position information of the droplet.

[0028] Based on the further improvement of the above method, the current equivalent capacitance value C of the microfluidic chip under test is calculated according to the following formula: d :

[0029]

[0030] Where U measureC is the measured value of the voltage division signal, A C is the amplification factor of the voltage divider signal measurement value, Z is the impedance of the voltage divider element, U is the effective value of the driving voltage signal, and ω is the angular frequency of the driving voltage signal.

[0031] Based on the further improvement of the above method, the effective value U of the driving voltage signal is calculated according to the following formula:

[0032]

[0033] Where U measureV is the measured value of the driving voltage signal, A V is the amplification factor of the driving voltage signal measurement value, and R2 / R1 is the attenuation coefficient.

[0034] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0035] 1. The droplet drive information feedback sensing circuit of the present invention will not affect the droplet drive work of the microfluidic chip under test when collecting signals, and can realize real-time monitoring and judgment of the motion state of the droplets during the droplet drive process, which is conducive to saving time.

[0036] 2. In the present invention, considering that the voltage divider signal at both ends of the voltage divider element has a large variation range, the voltage divider acquisition circuit adopts multiple parallel amplification channels with different amplification factors to collect signals. When the front-end voltage divider signal changes, the signal value of any amplification channel can be read in real time on demand, which not only realizes the range requirements for measuring voltage signals of different amplitudes, but also avoids the delay of signal acquisition, ensuring the speed and accuracy of signal reading.

[0037] 3. In the present invention, the back ends of multiple amplification channels of the voltage-dividing acquisition circuit are all processed and converted into DC signals using AC-DC conversion elements. Compared with the existing "point drawing method" of voltage signal point acquisition and resynthesis, it can more truly reflect the feedback voltage data and improve the accuracy of the feedback droplet driving information.

[0038] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0040] Figure 1 Schematic diagram of the principle of a droplet driving information feedback sensing circuit according to an embodiment of the present invention;

[0041] Figure 2It is a structural schematic diagram of a voltage division acquisition circuit according to an embodiment of the present invention;

[0042] Figure 3 Schematic diagram of the process of collecting voltage division signals according to an embodiment of the present invention;

[0043] Figure 4 It is a structural schematic diagram of a driving voltage acquisition circuit according to an embodiment of the present invention;

[0044] Figure 5 Schematic diagram of the process of collecting driving voltage according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0046] In the droplet drive control process of the microfluidic chip, it is necessary to monitor the droplet motion position state in real time to determine whether the chip is working normally. The embodiment of the present invention proposes a droplet drive information feedback sensing circuit and detection method based on the capacitance characteristics presented when the microfluidic chip is added with droplets.

[0047] An embodiment of the present invention provides a droplet driving information feedback sensing circuit, such as Figure 1-5 As shown in . The droplet drive information feedback sensing circuit includes: a microfluidic chip under test, a voltage divider element, a driving power supply and a voltage divider acquisition circuit. The microfluidic chip under test, the voltage divider element and the driving power supply are connected in series to form a loop. The voltage divider acquisition circuit includes: an acquisition module and a plurality of first amplification channels arranged in parallel, each of the first amplification channels includes a first amplifier and a first AC-DC conversion element connected in series, and the amplification factor of the first amplifier of each of the first amplification channels is different.

[0048] Among them, the acquisition module is used to acquire and attenuate the voltage divider signal at both ends of the voltage divider element, the first amplifier is used to amplify the attenuated voltage divider signal, and the first AC-DC element is used to convert the voltage divider signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage divider signal measurement value, and the current equivalent capacitance value of the microfluidic chip under test is calculated according to the collected voltage divider signal measurement value and the effective value of the driving voltage signal applied by the driving power supply to obtain the movement position information of the droplet.

[0049] Specifically, the above-mentioned voltage dividing element includes a voltage dividing resistor or a voltage dividing capacitor.

[0050] like Figure 1As shown in , the microfluidic chip of the embodiment of the present invention includes a first substrate and a second substrate arranged opposite to each other, a micro-droplet channel for accommodating droplets is formed between the first substrate and the second substrate, a common electrode is arranged on the first substrate, and a plurality of drive electrodes arranged at intervals along the droplet movement path are arranged on the second substrate, and a drive power supply provides a high-voltage AC signal required for droplet drive control, and the drive power supply is connected to all drive electrodes through a switch array, and the switch array selects the drive voltage signal, so that the drive voltage is applied to the corresponding drive electrode to drive the droplet to move. After the droplet is added to the micro-droplet channel of the microfluidic chip, the electrodes of the micro-droplet chip can be regarded as an equivalent capacitor, and the equivalent capacitance value changes during the movement of the micro-liquid.

[0051] In an embodiment of the present invention, the microfluidic chip to be tested, the voltage divider element and the driving power supply are connected in series to form a loop. The voltage divider signal at both ends of the voltage divider element with a fixed impedance value is measured by a voltage divider acquisition circuit, and the voltage between the electrodes of the micro-droplet chip can be calculated, and then its capacitance value can be obtained to determine the movement position information of the droplet.

[0052] When implementing, Figure 2 and Figure 3 As shown in , in the voltage-dividing acquisition circuit, the voltage-dividing signals at both ends of the voltage-dividing element are acquired through the acquisition module, and the acquired voltage-dividing signals are connected to multiple (for example, three) first amplification channels with different amplification factors in parallel. Multiple channels amplify the voltage-dividing signals at the same time. When the voltage-dividing signal at the front end changes, the signal value of any channel can be read as needed at any time, which not only realizes the range switching function required for measuring voltage signals of different amplitudes, but also ensures the speed and accuracy of signal reading. The back ends of multiple first amplification paths all use AC-to-DC elements for signal processing, complete the rectification and filtering to convert them into measurable DC signals, and the measured values ​​are more stable and reliable.

[0053] Compared with the prior art, the droplet drive information feedback sensing circuit of the present invention does not affect the droplet drive work of the microfluidic chip under test when collecting signals, and realizes real-time monitoring and judgment of the motion state of droplets during droplet drive, which is conducive to saving time.

[0054] Taking into account the large variation range of the voltage divider signal at both ends of the voltage divider element, the voltage divider acquisition circuit adopts multiple parallel amplification channels with different amplification factors for signal acquisition. When the front-end voltage divider signal changes, the signal value of any amplification channel can be read in real time on demand, which not only realizes the range requirements for measuring voltage signals of different amplitudes, but also avoids the delay of signal acquisition, thereby ensuring the speed and accuracy of signal reading.

[0055] At the same time, in the present invention, the back ends of multiple amplification channels of the voltage divider acquisition circuit are all processed and converted into DC signals using AC-DC conversion elements. Compared with the existing "point drawing method" of voltage signal point acquisition and resynthesis, it can more truly reflect the feedback voltage data and improve the accuracy of the feedback droplet driving information.

[0056] In a specific embodiment, the first AC-DC converter is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

[0057] Among them, the effective value chip can convert the AC voltage signal applied by the driving power supply into a measurable DC voltage signal through rectification and filtering, and the integration time of the effective value chip can be set, so as to effectively suppress the interference jitter and jump of the measurement signal, making the measurement value more stable and reliable.

[0058] During implementation, if the gain factor of the first amplifier of the first amplifier channel is larger, the effective value chip of the channel can be set to a longer integration time; if the gain factor of the first amplifier of the first amplifier channel is smaller, the effective value chip of the channel can be set to a shorter integration time.

[0059] Preferably, the voltage-dividing acquisition circuit further comprises: a first voltage follower. The first voltage follower is connected between the output end of the acquisition module and the input ends of the plurality of first amplification channels. Specifically, Figure 2 As shown in , the first voltage follower adopts an amplifier, and the first voltage follower is used for signal buffering and isolation to increase the load capacity.

[0060] In one embodiment, the droplet drive information feedback sensing circuit further includes: a processing module (e.g., a CPU processor). The processing module is respectively connected to the output ends of the plurality of first amplification channels, and the processing module selects a voltage division signal measurement value output by one of the first amplification channels as a valid measurement value according to a preset threshold value, which is used to calculate the current equivalent capacitance value of the microfluidic chip under test to obtain the motion position information of the droplet.

[0061] In this embodiment, a voltage division signal measurement value within a suitable range is automatically selected by the processing module for calculating the current equivalent capacitance value of the microfluidic chip under test to obtain the motion position information of the droplet, which is conducive to ensuring the accuracy of the feedback droplet driving information.

[0062] Specifically, the value range of the preset threshold value can be set to 1 / 3 to 2 / 3 of the driving voltage value, preferably 1 / 2 of the driving voltage value. In other words, in the process of collecting the voltage division signal, the voltage division measurement values ​​obtained by traversing different first amplification channels are preferably the voltage division signal measurement value closest to 1 / 2 of the driving voltage value as the effective measurement value.

[0063] Preferably, the processing module comprises an analog-to-digital conversion unit, and the analog-to-digital conversion unit is used to convert the voltage-divided signals output by the plurality of first amplification channels from analog signals into digital signals respectively.

[0064] Specifically, Figure 3 As shown in , the voltage-dividing acquisition circuit includes: three first amplifying channels connected in parallel. The amplification factors of the first amplifiers of the three first amplifying channels are respectively set to 1, 10 and 100 times.

[0065] In one embodiment, the droplet drive information feedback sensing circuit further includes: a drive voltage acquisition circuit. The drive voltage acquisition circuit includes: an attenuation module, a second amplifier, and a second AC-DC element, wherein the second attenuation module is used to acquire and attenuate the drive voltage signal applied by the drive power supply, the second amplifier is used to amplify the attenuated drive voltage signal, and the second AC-DC element is used to convert the amplified drive voltage signal from an AC signal to a DC signal and output it as a drive voltage signal measurement value. Wherein, the effective value of the drive voltage signal is calculated based on the drive voltage signal measurement value.

[0066] In an embodiment of the present invention, the droplet drive information feedback sensing circuit is divided into two paths for voltage signal acquisition as a whole, which are used to measure the driving voltage signal applied by the driving power supply and the voltage divider signal at both ends of the voltage divider element respectively. The equivalent capacitance of the chip after the droplet is added can be calculated through the collected signal measurement values, and then the real-time position state information during the droplet drive control process can be characterized.

[0067] The driving voltage acquisition circuit is used to collect and process the voltage signal of the driving power supply (high-voltage inverter power supply), and separate the driving voltage applied to the microfluidic chip into a single channel for signal acquisition. Figure 4 and Figure 5 as shown in .

[0068] It should be noted that the driving voltage signal applied by the driving power supply is a high-voltage AC signal. In order to measure the driving voltage signal, the driving voltage acquisition circuit of the embodiment of the present invention first attenuates the driving voltage signal through an attenuation module.

[0069] Specifically, Figure 5 As shown in , the attenuation coefficient of the attenuation module is set to 46.5 times, and the amplification factor of the second amplifier is set to 1 times.

[0070] Specifically, the second AC-DC converter is an effective value chip, and the integration time of the effective value chip is set according to the amplification factor of the corresponding second amplifier. The effective value chip can convert the AC voltage signal applied by the driving power supply into a measurable DC voltage signal through rectification and filtering, and the integration time of the effective value chip can be set, so as to effectively suppress the interference jitter and jump of the measurement signal, making the measurement value more stable and reliable.

[0071] Preferably, the driving voltage acquisition circuit further includes: a second voltage follower. The second voltage follower is connected between the output end of the attenuation module and the input end of the second amplifier. Specifically, Figure 4 As shown in , the second voltage follower adopts an amplifier, and the second voltage follower is used for signal buffering and isolation to increase the load capacity.

[0072] In an embodiment of the present invention, for the high-voltage AC signal of the drive control, the attenuation module uses resistance proportional attenuation to convert it into a signal within 5V. After the signal is attenuated, it is followed and amplified by the second voltage follower and the second amplifier to optimize the transmission signal quality. Then, the second AC to DC element (effective value chip) is used to rectify and filter the input signal and convert it into a DC signal. Finally, the analog-to-digital conversion unit (ADC) of the processing module completes the signal conversion and drives the voltage signal measurement value.

[0073] On the other hand, an embodiment of the present invention provides a method for detecting droplet driving information, which is implemented based on the droplet driving information feedback sensing circuit as described above. The method includes:

[0074] Step 1, respectively obtaining measurement values ​​of a plurality of divided voltage signals through a plurality of first amplification channels of a divided voltage acquisition circuit;

[0075] Step 2, selecting one of the voltage division signal measurement values ​​output by the first amplification channel as a valid measurement value according to a preset threshold;

[0076] Step 3, obtaining the effective value of the driving voltage signal applied by the driving power supply;

[0077] Step 4: Calculate the current equivalent capacitance value of the microfluidic chip under test according to the selected voltage division signal measurement value and the effective value of the driving voltage signal to determine the movement position information of the droplet in the microfluidic chip under test.

[0078] Specifically, in step 3, a driving voltage signal measurement value of a driving voltage signal applied by a driving power source is acquired through a driving voltage acquisition circuit.

[0079] Specifically, the current equivalent capacitance value C of the microfluidic chip under test is calculated according to the following formula: d:

[0080]

[0081] Where U measureC A is the measured value of the voltage division signal, which is obtained through the voltage division acquisition circuit; C is the amplification factor of the voltage divider signal measurement value; Z is the impedance of the voltage divider element; U is the effective value of the driving voltage signal; ω is the angular frequency of the driving voltage signal.

[0082] When the voltage divider element is a voltage divider resistor, Z = R C , R C is the resistance value of the voltage divider resistor. When the voltage divider element is a voltage divider capacitor, C C is the capacitance value of the voltage divider capacitor.

[0083] Specifically, the effective value U of the driving voltage signal is calculated according to the following formula:

[0084]

[0085] Where U measureV A is the measured value of the driving voltage signal, which is obtained through the driving voltage acquisition circuit; V is the amplification factor of the driving voltage signal measurement value; R2 / R1 is the attenuation coefficient. Figure 4 As shown in , R1 and R2 are the resistors in the attenuation module.

[0086] Furthermore, the current equivalent capacitance value C of the microfluidic chip under test d The total calculation formula is as follows:

[0087]

[0088] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0089] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A droplet drive information feedback sensing circuit, characterized in that: The droplet driving information feedback sensing circuit comprises: a microfluidic chip to be tested, a voltage dividing element, a driving power supply and a voltage dividing acquisition circuit. The microfluidic chip under test, the voltage divider element and the driving power supply are connected in series to form a loop, The voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, each of the first amplifying channels includes a first amplifier and a first AC-DC converter connected in series, and the amplification factor of the first amplifier of each first amplifying channel is different. The acquisition module is used to acquire the voltage division signal at both ends of the voltage division element, the first amplifier is used to amplify the acquired voltage division signal, and the first AC-DC conversion element is used to convert the voltage division signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage division signal measurement value. The current equivalent capacitance value of the microfluidic chip under test is calculated according to the collected measured value of the voltage division signal and the effective value of the driving voltage signal applied by the driving power supply to obtain the movement position information of the droplet.

2. The droplet drive information feedback sensing circuit according to claim 1, characterized in that: The first AC-to-DC element is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

3. The droplet drive information feedback sensing circuit according to claim 1 or 2, characterized in that: The voltage dividing element includes a voltage dividing resistor or a voltage dividing capacitor.

4. The droplet drive information feedback sensing circuit according to claim 1 or 2, characterized in that: The voltage-dividing acquisition circuit further includes: a first voltage follower, The first voltage follower is connected between the output end of the acquisition module and the input ends of the plurality of first amplification channels.

5. The droplet drive information feedback sensing circuit according to claim 1 or 2, characterized in that: The droplet driving information feedback sensing circuit further includes: a processing module, The processing module is respectively connected to the output ends of the plurality of first amplification channels. The processing module selects a voltage division signal measurement value output by one of the first amplification channels as a valid measurement value according to a preset threshold value, which is used to calculate the current equivalent capacitance value of the microfluidic chip under test to obtain the movement position information of the droplet.

6. The droplet drive information feedback sensing circuit according to claim 1 or 2, characterized in that: The droplet driving information feedback sensing circuit also includes: a driving voltage acquisition circuit, The driving voltage acquisition circuit includes: an attenuation module, a second amplifier and a second AC-DC conversion element, The attenuation module is used to collect and attenuate the driving voltage signal applied by the driving power supply, the second amplifier is used to amplify the attenuated driving voltage signal, and the second AC-DC element is used to convert the amplified driving voltage signal from an AC signal to a DC signal and output it as a driving voltage signal measurement value; Wherein, the effective value of the driving voltage signal is calculated according to the measured value of the driving voltage signal.

7. The droplet driving information feedback sensing circuit according to claim 6, characterized in that: The driving voltage collection circuit further includes: a second voltage follower, The second voltage follower is connected between the output terminal of the attenuation module and the input terminal of the second amplifier.

8. A method for detecting droplet driving information, implemented based on the droplet driving information feedback sensing circuit according to any one of claims 1 to 7, characterized in that: The method comprises: Acquire measurement values ​​of a plurality of divided voltage signals respectively through a plurality of first amplification channels of the divided voltage acquisition circuit; Selecting a voltage division signal measurement value output by one of the first amplification channels as a valid measurement value according to a preset threshold; Acquire the effective value of the driving voltage signal applied by the driving power supply; The current equivalent capacitance value of the measured microfluidic chip is calculated according to the selected measured value of the voltage division signal and the effective value of the driving voltage signal to obtain the movement position information of the droplet.

9. The method for detecting droplet driving information according to claim 8, characterized in that: Calculate the current equivalent capacitance value C of the microfluidic chip under test according to the following formula d : Where U measureC is the measured value of the voltage division signal, A C is the amplification factor of the voltage divider signal measurement value, Z is the impedance of the voltage divider element, U is the effective value of the driving voltage signal, and ω is the angular frequency of the driving voltage signal.

10. The droplet driving information detection method according to claim 9, characterized in that: The effective value U of the driving voltage signal is calculated according to the following formula: Where U measureV is the measured value of the driving voltage signal, A V is the amplification factor of the driving voltage signal measurement value, and R2 / R1 is the attenuation coefficient.

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