Medical device and electrical connection detection system therefor

Abstract

The application discloses a medical device and an electric connection detection system thereof. The medical device comprises at least a cartridge and a cartridge bin. The cartridge is provided with a printed circuit board. The printed circuit board comprises a first surface for realizing an electrowetting function and driving droplet movement and a second surface corresponding to the first surface. The first surface is provided with a plurality of electrode pairs. The second surface is provided with a plurality of pad pairs and a plurality of signal coupling conductor pairs. One end of the signal coupling conductor pair is connected with the pad pair, and the other end is connected with the electrode pair. In the cartridge, the signal coupling pair comprising parallel conductors is used to realize the electric connection between the pad pair and the electrode pair. The conductor pair can improve the coupling voltage, reduce the impedance value, and increase the impedance value difference between the normal electrode pair and the abnormal electrode. Thus, the medical device can easily detect the abnormal electrode, and the detection error and reagent waste are avoided.

Description

Technical Field

[0001] This application relates to the field of instrumentation technology, and more specifically, to a medical device and its electrical connection detection system. Background Technology

[0002] Microfluidics, also known as micro-volume total analysis systems and lab-on-a-chip technology, offers advantages such as miniaturization, high throughput, low sample volume requirements, and faster processing speeds. The development of dielectric electrowetting technology has facilitated the commercialization of microscale liquid handling technologies based on printed circuit board (PCB) digital microfluidics.

[0003] A typical electrical connection testing system usually includes one or more cartridge compartments and corresponding control units. The cartridge compartments are used to hold the inserted cartridges, and the cartridges are electrically connected to each other via spring pins. The control unit also includes a central processing module and a display interface. The central processing module is used to control the insertion and ejection of cartridges and the acquisition and processing of data, while the display interface is used to display the testing process and results.

[0004] The lower part of the cartridge houses a printed circuit board (PCB) for electrowetting-driven liquid movement. The top layer of this PCB includes multiple electrodes to achieve electrowetting and thus drive liquid movement. The bottom of the PCB is electrically connected to the cartridge compartment via spring pins. The central processing unit (CPU) provides electrical signals to the electrodes on the PCB via these spring pins. If the electrical connection between the cartridge compartment and the cartridge is incorrect, the correct electrical signal cannot be provided to the electrodes on the cartridge, leading to electrowetting failure. Consequently, the detection system cannot properly process the reagent, resulting in detection errors and reagent waste.

[0005] To avoid detection errors, a pre-test should be performed after the card cartridge is inserted into the cartridge compartment, but before the device officially starts testing. This test assesses whether the correct electrical connection has been established between the card cartridge and the cartridge compartment. After the self-test is completed, reagent testing should be performed to avoid detection errors and reagent waste. Summary of the Invention

[0006] In view of this, this application provides a medical device and its electrical connection detection system to avoid detection errors and waste of reagents.

[0007] To achieve the above objectives, the following solution is proposed:

[0008] A medical device, characterized in that it includes a cartridge configured with a printed circuit board, the printed circuit board including a first surface for realizing electrowetting function and driving droplet movement and a second surface corresponding to the first surface, wherein:

[0009] The first surface is provided with multiple sets of electrode pairs;

[0010] The second surface is provided with multiple pad pairs and multiple signal coupling wire pairs;

[0011] One end of the signal coupling wire pair is connected to the pad pair, and the other end is connected to the electrode pair.

[0012] Optionally, each pair of coupling wires includes two parallel wires, the distance between the two wires being constant and their lengths being equal.

[0013] Optionally, the distance between the two wires is 4mil-12mil.

[0014] Optionally, the length of the parallel conductor pair is greater than 20 mm.

[0015] An electrical connection detection system is applied to the aforementioned medical device. The electrical connection detection system includes a cartridge compartment and a control unit connected to the cartridge compartment, wherein:

[0016] The cartridge compartment is used to hold the inserted cartridge and includes multiple sets of probes, which are connected to the corresponding pads for signal connection.

[0017] The control unit is used to output a high-frequency voltage signal to the probe and to process the feedback signal fed back by the probe to obtain the detection result.

[0018] Optionally, the probe is a spring probe or a test probe.

[0019] Optionally, the control unit includes a signal acquisition circuit and a signal processing module, wherein:

[0020] The signal acquisition circuit is used to acquire the feedback signal and output the feedback signal to the signal processing module;

[0021] The signal processing module is used to process the feedback signal to obtain the detection result.

[0022] Optionally, the signal acquisition circuit includes:

[0023] A high-voltage capacitor connected at one end to the probe signal;

[0024] The negative terminal is connected to the other end of the high-voltage capacitor, and the positive terminal of the clamping diode is grounded.

[0025] A multiplexed switch whose input terminal is connected to the negative terminal of the clamping diode;

[0026] A high-speed operational amplifier whose non-inverting input is connected to the output of the multiplexer, and whose inverting input and output are connected.

[0027] A second-order bandpass filter with one end connected to the output of the high-speed operational amplifier;

[0028] The input terminal is connected to the other end of the second-order bandpass filter via a signal acquisition and processing chip.

[0029] As can be seen from the above technical solution, this application discloses a medical device and its electrical connection detection system. The medical device includes a cartridge and a cartridge compartment. The cartridge is equipped with a printed circuit board, which includes a first surface for realizing electrowetting and driving droplet movement, and a second surface corresponding to the first surface. The first surface is provided with multiple sets of electrode pairs; the second surface is provided with multiple pad pairs and multiple signal coupling wire pairs; one end of each signal coupling wire pair is connected to a pad pair, and the other end is connected to an electrode pair. The cartridge in this application utilizes signal coupling wire pairs including parallel wires to realize the electrical connection between the pad pairs and the electrode pairs. These wire pairs can increase the coupling voltage and reduce the impedance value, thereby increasing the difference between the impedance value of a normal electrode pair and the impedance value of an abnormally connected electrode. This allows the system to easily detect abnormal electrodes, avoiding detection errors and reagent waste. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the first surface of the printed circuit board of the card holder according to an embodiment of this application;

[0032] Figure 2 This is a schematic diagram of the second surface of the printed circuit board of the card holder according to an embodiment of this application;

[0033] Figure 3 This is a schematic diagram of the electrical connections of the printed circuit board of the card holder according to an embodiment of this application;

[0034] Figure 4 This is a flowchart of the electrical connection detection system in the embodiments of this application;

[0035] Figure 5 The impedance values ​​of different electrode pairs in the same card holder according to embodiments of this application;

[0036] Figure 6 This is a schematic diagram of a signal acquisition circuit according to an embodiment of this application. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0038] Figure 1 This is a schematic diagram of a printed circuit board for a card holder according to an embodiment of this application.

[0039] This embodiment provides a medical device including a cartridge and a cartridge compartment for housing the cartridge, and also includes an electrical connection detection system. The cartridge is used to carry specific reagents, including biological reagents and chemical reagents, enabling the medical device to detect these reagents. The cartridge includes a housing and a printed circuit board disposed within the housing. Generally, a printed circuit board is an insulating substrate on which corresponding wires, electrodes, and contacts are laid. Its shape is generally a flat plate with two surfaces: a top and a bottom. In typical applications, the top, bottom, front, and back surfaces are not practically significant; therefore, this application refers to the two surfaces as the first surface and the second surface.

[0040] Multiple sets of electrode pairs 20 are disposed on the first surface of the printed circuit board 10, such as Figure 1 As shown, an electrode pair consists of two electrodes. The electrode pairs are arranged in pairs according to a specific pattern and order. When the cartridge is inserted into the cartridge compartment, the electrical connection detection system performs a pre-self-test on the electrode pairs in the cartridge to determine whether each electrode in the cartridge has achieved a true electrical connection with the cartridge compartment. After the self-test, when the cartridge is used for droplet actuation, the reagent droplet rests on the electrodes, and each electrode operates independently, performing its respective function. As needed, the reagent droplet can be controlled to move along the electrodes on the printed circuit board according to a predetermined pattern and speed.

[0041] Multiple pad pairs 30 and multiple signal coupling wire pairs 40 are provided on the second surface of the printed circuit board, such as Figure 2 As shown. Signal coupling wire pairs are used to connect corresponding pads to electrode pairs together, such as... Figure 3 As shown, one end of the signal coupling wire pair is connected to the pad pair, and the other end is connected to the electrode pair. Furthermore, the electrode pair, signal coupling wire pair, and pad pair in this application can be disposed on the same side of the printed circuit board, i.e., all on the first surface or all on the second surface, in order to reduce processing difficulty and cost while meeting functional requirements.

[0042] The signal coupling conductor pair in this application comprises two parallel conductors of equal length. Here, "parallel" means that the distance between the two conductors on the printed circuit board remains constant at any position. Furthermore, all signal coupling conductors on the printed circuit board have the same length. In this application, the distance between the two conductors is 4 mil to 12 mil; the length of the parallel conductor pair is greater than 20 millimeters.

[0043] Current technologies rely solely on the coupling between electrodes and the upper plate, or the generation of voltage or current signals between two electrodes, to test impedance. However, due to electrode designs below 5mm, the coupling signal is too weak and susceptible to interference. Furthermore, the upper plate's impedance varies significantly due to manufacturing limitations, making standardization difficult. When the spring pin experiences insufficient contact due to dust or spring failure, the impedance value changes very little relative to a larger value, making it difficult to detect. Even after refitting the impedance data or using other algorithms, considerable errors remain, leading to inaccurate test results. Additionally, there are differences and variability between cartridge compartments and between the printed circuit boards (PCBs) on the cartridges. For example, a measurement (voltage or impedance) generated when a cartridge is inserted into a compartment during normal operation might equal a measurement generated by a poor connection between another cartridge and its compartment. Therefore, measurements generated between different cartridges and compartments cannot accurately represent the quality of the results. This could lead to situations where poor connections between cartridges and compartments are tolerated, while good connections fail to function, resulting in greater waste or errors.

[0044] In this application, equal-length traces are used, with the two conductors of each signal coupling wire pair being of equal length. The signal coupling wire pairs of different electrode pairs are also of equal length, ensuring that the impedance data of each electrode pair in the card case is equal or similar. In actual testing, different card cases were tested, and the average and precision of the impedance values ​​of each electrode pair in the same card case were measured. The difference between the impedance data of each electrode pair and the average value was within 5‰, as shown in the table below.

[0045]

[0046]

[0047] During droplet actuation, each electrode operates independently, performing its respective function. During pre-detection, two electrodes are paired, with a spring connector pin transmitting a square wave drive signal (frequency 1K-100KHz, peak-to-peak voltage 60-300V) to each electrode. This drive circuit is called the drive terminal. The drive signal is coupled to the other electrode (the other electrode in the electrode pair) via a signal coupling wire. This sensing circuit is called the detection terminal. The detection terminal receives a coupled voltage signal, which is transmitted through the detection terminal trace to the pad contacted by the spring pin, and from there to the signal processing circuit via the spring pin. After filtering, gain processing, and digital-to-analog conversion of the detection terminal voltage signal, an equal or similar impedance data is obtained. The impedance data generated by each pair of electrodes on the cartridge printed circuit board are organized into a data stream. This data stream is analyzed, and its standard deviation is calculated. If the standard deviation exceeds a set value, it indicates an abnormal impedance value for the cartridge, suggesting a lack of proper connection to the device.

[0048] In specific tests, the following methods are used: Figure 4 The process illustrated involves the control unit of the detection system generating a high-frequency square wave voltage signal, which is transmitted to the electrodes of the cartridge via a spring pin connected to a printed circuit board (PCB) trace. This high-frequency voltage signal couples onto another PCB trace, generating a voltage signal of the same frequency. This voltage signal is then transmitted to another spring pin via the PCB trace. This voltage signal is then fed to the processing chip via the spring pin to obtain a voltage or impedance value. If this data exceeds the normal threshold, it indicates that one or both electrodes in this pair may be faulty. The cartridge can then be reinserted into the same or another cartridge compartment for testing. If the data from the electrodes at the same location also exceeds the normal threshold, the cartridge can be determined to be damaged.

[0049] Voltage coupling signal Vvictim and drive circuit voltage signal V aggressor The relationship between them is shown in the following formula:

[0050]

[0051] Where K is a constant whose value is always less than 1, and depends on the rise time of the circuit and the length of the parallel trace on the PCB. 2 D is the product of the heights of the parallel conductors. 2 It is the product of the direct distances between the centerlines of parallel conductors.

[0052] like Figure 5As shown, in the entire data stream, there are two points representing the impedance values ​​when the electrode pair is not properly connected. In practice, if the standard deviation of the entire data stream is greater than a set value, or if these two largest data points are selected, the standard deviation is recalculated. If the standard deviation is less than the set value, it can be determined that the card holder and the device are not properly electrically connected. This method ensures that the differences between different card holders do not affect the judgment of specific values, each data point becomes predictable, and there is no need to sort the data stream again, thus improving the accuracy, simplicity, and precision of the judgment.

[0053] As can be seen from the above technical solution, this application provides a medical device and its electrical connection detection system. This system includes at least a cartridge and a cartridge compartment. The cartridge is equipped with a printed circuit board, which includes a first surface for implementing electrowetting and driving droplet movement, and a second surface corresponding to the first surface. The first surface is provided with multiple sets of electrode pairs; the second surface is provided with multiple pad pairs and multiple signal coupling wire pairs; one end of each signal coupling wire pair is connected to a pad pair, and the other end is connected to an electrode pair. The cartridge in this application utilizes signal coupling wire pairs including parallel wires to achieve electrical connection between the pad pairs and the electrode pairs. These wire pairs can increase the coupling voltage and reduce the impedance value, thus increasing the difference between the impedance value of a normal electrode pair and the impedance value of an abnormally connected electrode. This allows the system to easily detect abnormal electrodes, avoiding detection errors and reagent waste.

[0054] Additionally, this application provides an electrical connection detection system, which includes a cartridge compartment for accommodating the aforementioned cartridge and a control unit connected to the cartridge compartment. The cartridge compartment is equipped with multiple sets of probes, which can be spring probes or test probes, for connecting to pads when the cartridge is inserted. The control unit is used to input a high-frequency voltage signal to the probes through its signal generation circuit and obtain a detection result based on the obtained feedback signal. The control unit includes at least a signal acquisition circuit and a signal processing circuit; the signal acquisition circuit is used to acquire feedback signals from different electrode pairs, and the signal processing circuit is used to process the feedback signal to obtain the detection result.

[0055] The signal acquisition circuit includes a high-voltage capacitor C, a clamping diode TVS, a multiplexer 102, a high-speed operational amplifier 103, a second-order bandpass filter 201, and a signal acquisition and processing chip 202, such as... Figure 6As shown. One end of the high-voltage capacitor serves as signal input terminal 101, used for connection to different probes. The other end of the high-voltage capacitor is connected to the negative terminal of the clamping diode, whose positive terminal is grounded. The other end of the high-voltage capacitor, or the negative terminal of the clamping diode, is also connected to one input terminal of the multiplexer. The non-inverting input terminal of the high-speed operational amplifier is connected to the output terminal of the multiplexer, and the inverting input terminal and output terminal of the high-speed operational amplifier are connected to form a feedback circuit. The output terminal of the high-speed operational amplifier is connected to one end of a second-order bandpass filter, and the other end of the second-order bandpass filter is connected to the signal acquisition and processing chip.

[0056] High-voltage capacitors effectively remove DC and low-frequency voltage signals, while clamping diodes protect the multiplexer chip from damage by high-voltage signals. The multiplexer chip has a single-channel on-resistance of 4 ohms, a 0.5Ω resistance flatness, and a leakage current of only 1nA. A high-speed operational amplifier forms a voltage follower, theoretically allowing for infinite input impedance and infinitesimal output impedance, effectively reducing losses of coupled voltage signals in the preceding circuitry and improving the circuit's load-carrying capacity. A second-order bandpass filter, composed of an operational amplifier, capacitors, and resistors, effectively filters out power frequency interference signals and their noise. After signal acquisition, the signal is processed directly by a microcontroller, or by an AD chip or impedance chip, and then further processed by the microcontroller to convert the original, interference-free voltage value into impedance data.

[0057] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0058] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0059] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0060] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An electrical connection detection system, characterized in that, The device includes a card holder, the card holder being configured with a printed circuit board, the printed circuit board including a first surface for implementing electrowetting function and driving droplet movement and a second surface corresponding to the first surface, wherein: The first surface is provided with multiple sets of electrode pairs; The second surface is provided with multiple pad pairs and multiple signal coupling wire pairs of equal length; One end of the signal coupling wire pair is connected to the pad pair, and the other end is connected to the electrode pair; Each pair of coupling wires includes two parallel wires, the distance between the two wires being constant and their lengths being equal; The distance between the two conductors is 4 mil to 12 mil; The length of the signal coupling wire pair is greater than 20 mm.

2. The electrical connection detection system as described in claim 1, characterized in that, It also includes a card holder compartment and a control unit connected to the card holder compartment, wherein: The cartridge compartment is used to hold the inserted cartridge and includes multiple sets of probes, which are connected to the corresponding pads for signal transmission. The control unit is used to output a high-frequency voltage signal to the probe and to process the feedback signal fed back by the probe to obtain the detection result.

3. The electrical connection detection system as described in claim 2, characterized in that, The probe is a spring probe or a test probe.

4. The electrical connection detection system as described in claim 2, characterized in that, The control unit includes a signal acquisition circuit and a signal processing module, wherein: The signal acquisition circuit is used to acquire the feedback signal and output the feedback signal to the signal processing module; The signal processing module is used to process the feedback signal to obtain the detection result.

5. The electrical connection detection system as described in claim 4, characterized in that, The signal acquisition circuit includes: A high-voltage capacitor connected at one end to the probe signal; The negative terminal is connected to the other end of the high-voltage capacitor, and the positive terminal of the clamping diode is grounded. A multiplexed switch whose input terminal is connected to the negative terminal of the clamping diode; A high-speed operational amplifier whose non-inverting input is connected to the output of the multiplexer, and whose inverting input and output are connected. A second-order bandpass filter with one end connected to the output of the high-speed operational amplifier; The input terminal is connected to the other end of the second-order bandpass filter via a signal acquisition and processing chip.

Images