Power supply isolation circuit and anesthesia depth monitor

Abstract

The utility model provides a power supply isolation circuit and an anesthesia depth monitor comprising the same. The power supply isolation circuit is connected between a power supply circuit and an electroencephalogram acquisition circuit in the anesthesia depth monitor, and comprises an input protection module, a first filtering module, an isolation module and a second filtering module which are connected in sequence, high-frequency and external interference signals between the power supply circuit and the electroencephalogram acquisition circuit are filtered and isolated through the first filtering module, the isolation module and the second filtering module, and meanwhile, connection between the power supply circuit and the electroencephalogram acquisition circuit can be cut off when the voltage output by the power supply circuit is larger than a preset threshold value. The accuracy of the electroencephalogram signals collected by the electroencephalogram collection circuit is improved through the power source isolation circuit, the influence of external signals on the monitoring result of the anesthesia depth monitor can be effectively avoided, the monitoring result is more accurate and reliable, and the anesthesia depth monitor and a patient are protected.

Description

Technical Field

[0001] The utility model relates to the technical field of electroencephalogram signal acquisition, and particularly relates to a power isolation circuit and an anesthesia depth monitor. Background Art

[0002] During surgical operations, the anesthesia process before the operation is extremely important. Once the anesthesia dosage is incorrect or the operation time cannot be well controlled, it will cause great pain to the patient during the operation. Once the anesthesia fails and the patient twitches due to pain, it will seriously affect the operation process and cause medical accidents. The anesthesia depth monitor is a reliable way to realize the objective monitoring method of anesthesia depth. The observation and management of anesthesia depth are one of the main tasks during anesthesia. Currently, anesthesia is clinically divided into light anesthesia stage, surgical anesthesia, and deep anesthesia. Detecting anesthesia depth by electroencephalogram activity is one of the recent research directions.

[0003] The main signal source of the anesthesia depth monitor is to collect electroencephalogram signals (EEG signals). EEG signals are very weak, generally at the microvolt (uV) level. And due to the electroencephalogram lead methods (including monopolar lead method, bipolar lead method, and triangular lead method), it is very easy to be interfered by external environments such as the power supply, grounding loop, and environmental noise. The EEG signals collected by the anesthesia depth monitor are extremely unstable. If the interfered signals are not processed, it will greatly affect the measurement of anesthesia depth-related parameters, which may lead to difficulties in the operation or accidents. In severe cases, it may even cause electric shock hazards to the patient. Summary of the Utility Model

[0004] The utility model provides a power isolation circuit and an anesthesia depth monitor, which can solve the technical problem that the existing anesthesia depth monitor is easily interfered by the external environment when collecting electroencephalogram signals, affecting the accuracy of the collected signals.

[0005] In the first aspect, an embodiment of the present application provides a power isolation circuit, which is applied to an electroencephalogram acquisition device. The electroencephalogram acquisition device includes a power supply circuit and an electroencephalogram acquisition circuit. The power isolation circuit includes an input protection module, a first filtering module, an isolation module, and a second filtering module that are connected in sequence.

[0006] The input end of the input protection module is connected to the output end of the power supply circuit, and the output end of the second filtering module is connected to the input end of the electroencephalogram acquisition circuit.

[0007] Among them, the input protection module is used to cut off the connection between the power supply circuit and the electroencephalogram acquisition circuit when the voltage output by the power supply circuit is greater than a preset threshold. The first filtering module and the second filtering module are used to filter out high-frequency interference in the voltage output by the power supply circuit. The isolation module is used to isolate the electrical interference signals between the power supply circuit and the electroencephalogram acquisition circuit.

[0008] In some embodiments, the input protection module includes a zener diode D101, a zener diode D102, and a fuse F101;

[0009] The first end of the zener diode D101 is connected to the input end of the input protection module; the first end of the zener diode D102 is connected to the second end of the zener diode D101, and the second end of the zener diode D102 is connected to a preset voltage terminal; the first end of the fuse F101 is connected to the second end of the zener diode D101, and the second end of the fuse F101 is connected to the output end of the input protection module.

[0010] In some embodiments, the first filtering module is a CL-type low-pass filter, including an inductor L101 and a capacitor C101;

[0011] The first end of the inductor L101 is connected to the input end of the first filtering module, and the second end of the inductor L101 is connected to the output end of the first filtering module; the first end of the capacitor C101 is connected to the first end of the inductor L101, and the second end of the capacitor C101 is connected to a preset voltage terminal.

[0012] In some embodiments, the second filtering module all adopts an LC low-pass filter, including an inductor L102 and a capacitor C102;

[0013] The first end of the inductor L102 is connected to the input end of the second filtering module, and the second end of the inductor L102 is connected to the output end of the second filtering module; the first end of the capacitor C102 is connected to the second end of the inductor L102, and the second end of the capacitor C102 is connected to a preset voltage terminal.

[0014] In some embodiments, the low-pass cut-off frequencies of the first filtering module and the second filtering module are greater than 3000 Hz.

[0015] In some embodiments, the isolation module is a digital isolation chip.

[0016] In some embodiments, the isolation voltage of the isolation module is greater than 5200 V, the isolation resistance is greater than 20 GΩ, and the isolation capacitance is less than or equal to 10 pF.

[0017] In some embodiments, the model of the isolation module is RP-0505S.

[0018] In some embodiments, the power isolation circuit further includes an output load module connected between the output end of the second filtering module and the input end of the electroencephalogram acquisition circuit;

[0019] The output load module includes a resistor R101 and a resistor R102 connected in parallel; wherein, the first ends of the resistor R101 and the resistor R102 are both connected to the output end of the output load module, and the second ends of the resistor R101 and the resistor R102 are both connected to a preset voltage terminal.

[0020] In a second aspect, an embodiment of the present application provides an anesthesia depth monitor, including a power supply circuit, an electroencephalogram acquisition circuit, a functional module, and the power supply isolation circuit as described in any of the above embodiments;

[0021] The power supply isolation circuit is connected between the power supply circuit and the electroencephalogram acquisition circuit, and is used to isolate the interference signals between the power supply circuit and the electroencephalogram acquisition circuit.

[0022] The power supply isolation circuit provided by the embodiment of the present application and the anesthesia depth monitor including the power supply isolation circuit are connected between the power supply circuit and the electroencephalogram acquisition circuit in the anesthesia depth monitor. The power supply isolation circuit includes an input protection module, a first filtering module, an isolation module, and a second filtering module connected in sequence. The first filtering module, the isolation module, and the second filtering module are used to filter and isolate the high-frequency and external interference signals between the power supply circuit and the electroencephalogram acquisition circuit. At the same time, when the voltage output by the power supply circuit is greater than a preset threshold, the connection between the power supply circuit and the electroencephalogram acquisition circuit is cut off. The present application improves the accuracy of the electroencephalogram signals collected by the electroencephalogram acquisition circuit through the power supply isolation circuit, can effectively avoid the influence of external signals on the monitoring results of the anesthesia depth monitor, so that the monitoring results are more accurate and reliable, and plays a protective role for both the anesthesia depth monitor and the patient. Description of the Drawings

[0023] The drawings here are incorporated into the description and form a part of this description, showing embodiments consistent with the present application, and are used together with the description to explain the principles of the present application.

[0024] Figure 1 It is a structural diagram of an anesthesia depth monitor provided by an embodiment of the present application;

[0025] Figure 2 It is a structural block diagram of a power supply isolation circuit provided by an embodiment of the present application;

[0026] Figure 3 It is a circuit diagram of a power supply isolation circuit provided by an embodiment of the present application.

[0027] Through the above drawings, the clear embodiments of the present application have been shown, and there will be more detailed descriptions later. These drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed Embodiments

[0028] The present application will be further described in detail below in conjunction with the accompanying drawings through specific embodiments. Similar elements in different embodiments are denoted by related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification to avoid overwhelming the core part of the present application with excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and general technical knowledge in the art.

[0029] In addition, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in an obvious manner by those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean a necessary sequence, unless it is stated that a certain sequence must be followed.

[0030] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein. The objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims means at least one of the connected objects. The character " / ", generally represents an "or" relationship between the related objects before and after. And the "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).

[0031] This application intends to use a current transformer to replace the traditional sampling resistor for sampling the transmitted current and / or transmitted voltage. Based on the electromagnetic induction principle of the current transformer, after the input interface and the output interface are connected to the terminal, the current and / or voltage between the input interface and the output interface are induced to generate corresponding electrical signals, and the electrical signals are output to the control module to directly sample the transmitted current and / or transmitted voltage of the data line in the working state. In the traditional sampling through a sampling resistor, due to the environmental temperature or the heat generated by itself, the temperature drift phenomenon of the resistance value occurs. After the change in the sampling accuracy is amplified, the deviation value will be amplified sharply, resulting in a decrease in the sampling accuracy and the inability to accurately monitor the current value or voltage value.

[0032] The following will specifically describe the technical solutions of this application and how the technical solutions of this application solve the above technical problems with specific embodiments. These specific embodiments below can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will be described below with reference to the drawings.

[0033] Figure 1 The structure diagram of an anesthesia depth monitor provided by an embodiment of this application is shown as Figure 1 As shown, the anesthesia depth monitor provided by the embodiment of this application includes a power supply circuit 110, an electroencephalogram (EEG) acquisition circuit 120, a function module 130, and a power isolation circuit 140 connected between the power supply circuit 110 and the EEG acquisition circuit 120.

[0034] In this embodiment, the anesthesia depth monitor uses a standard 220V power supply as the input power supply and simultaneously uses a medical special adapter to output a DC5V / 3A current to provide DC power for the EEG acquisition circuit 120 and the function module 130 of the anesthesia depth monitor. The power supply circuit 110 is used to convert the externally input high-voltage power supply into a DC current output through DC / DC conversion.

[0035] In some embodiments, the EEG acquisition circuit 120 includes acquisition electrodes and an acquisition module, which are used to acquire the EEG signals of the patient through the acquisition electrodes and provide a monitoring basis for the function module 130.

[0036] In some embodiments, the functional module 130 of the anesthesia depth monitor at least includes functional units such as a sensor unit, a signal processing unit, a data analysis unit, a display unit, an alarm and alert unit, and a data storage and export unit. It can monitor the anesthesia depth of patients in real time during surgery. By collecting electroencephalogram (EEG) signals, electromyogram (EMG) signals, etc., and performing data processing to form quantitative indicators, it displays the anesthesia depth index to help doctors precisely manage anesthesia. By monitoring the patient's vital signs and changes in anesthesia depth, the anesthesia depth monitor can pre-judge any problems that occur during surgery, provide risk warnings for doctors, and reduce surgical risks caused by too deep or too shallow anesthesia. At the same time, through real-time monitoring and precise management, the anesthesia depth monitor can improve the safety of surgical patients and reduce the occurrence of postoperative complications and adverse events. The data storage and export function also facilitates postoperative analysis and research.

[0037] In this embodiment, the power isolation circuit 140 connected between the power supply circuit 110 and the EEG acquisition circuit 120 is mainly used to isolate the interference signals between the power supply circuit 110 and the EEG acquisition circuit 120, so as to ensure that the EEG signals collected by the EEG acquisition circuit 120 have high accuracy and provide strong support for subsequent data analysis.

[0038] It should be noted that since the main improvement point of the embodiment of this application is aimed at the structure of the power isolation circuit 140, therefore, the specific structures of the power supply circuit 110, the EEG acquisition circuit 120, and the functional module 130, as well as the implementation manner of the functional module 130 are not limited in this application embodiment. Therefore, the other structures of the anesthesia depth monitor provided in the embodiment of this application will not be elaborated here.

[0039] Next, the structure and composition of the power isolation circuit 140 will be specifically described.

[0040] Figure 2 It is a structural block diagram of the power isolation circuit provided in an embodiment of this application. As Figure 2 shown, the power isolation circuit 140 provided in the embodiment of this application includes an input protection module 210, a first filtering module 220, an isolation module 230, a second filtering module 240, and an output load module 250 that are connected in sequence.

[0041] In this embodiment, the input end of the input protection module is connected to the output end of the power supply circuit 110, and the output end of the output load module 250 is connected to the input end of the EEG acquisition circuit 120. The first filtering module, the isolation module, and the second filtering module are used to filter and isolate the high-frequency and external interference signals between the power supply circuit 110 and the EEG acquisition circuit 120.

[0042] Specifically, the input protection module is used to cut off the connection between the power supply circuit 110 and the electroencephalogram acquisition circuit 120 when the voltage output by the power supply circuit 110 is greater than a preset threshold; the first filtering module and the second filtering module are used to filter out high-frequency interference in the voltage output by the power supply circuit 110; the isolation module is used to isolate the electrical interference signal between the power supply circuit 110 and the electroencephalogram acquisition circuit 120; the output load module is used to stably output voltage / current, adjust the voltage / current output by the power isolation circuit 140, prevent high voltage, protect the components in the circuit, and improve the stability of the circuit.

[0043] Figure 3 The circuit diagram of the power isolation circuit provided by an embodiment of the present application is shown as Figure 3 shown. In the power isolation circuit 140 provided in this embodiment, the input protection module includes a voltage stabilizing diode D101, a voltage stabilizing diode D102, and a fuse F101.

[0044] Specifically, the first end of the voltage stabilizing diode D101 is connected to the input end of the input protection module; the first end of the voltage stabilizing diode D102 is connected to the second end of the voltage stabilizing diode D101, and the second end of the voltage stabilizing diode D102 is connected to the preset voltage terminal; the first end of the fuse F101 is connected to the second end of the voltage stabilizing diode D101, and the second end of the fuse F101 is connected to the output end of the input protection module.

[0045] In some embodiments, since the frequency band range of the electroencephalogram signal is generally 0.5 - 3000 Hz, the first filtering module and the second filtering module adopt low-pass filters, which can transmit the direct current or low-frequency signals output by the power supply circuit 110, attenuate the high-frequency signals, and achieve the purpose of filtering out high-frequency noise in the signals. The current output by the power supply circuit 110 is a relatively pure direct current.

[0046] In this embodiment, the first filtering module is a CL type low-pass filter, including an inductor L101 and a capacitor C101. The capacitor C101 is arranged in front and the inductor L101 is arranged behind, and its characteristic is high input impedance and low output impedance. Specifically, the first end of the inductor L101 is connected to the input end of the first filtering module, and the second end of the inductor L101 is connected to the output end of the first filtering module; the first end of the capacitor C101 is connected to the first end of the inductor L101, and the second end of the capacitor C101 is connected to the preset voltage terminal.

[0047] In this embodiment, the second filtering module all adopts an LC low-pass filter, including an inductor L102 and a capacitor C102. The inductor L102 is arranged in the front and the capacitor C102 is arranged in the back, and its characteristic is that the input impedance is low and the output impedance is high. Specifically, the first end of the inductor L102 is connected to the input end of the second filtering module, and the second end of the inductor L102 is connected to the output end of the second filtering module; the first end of the capacitor C102 is connected to the second end of the inductor L102, and the second end of the capacitor C102 is connected to the preset voltage terminal.

[0048] When the high-frequency interference signal and the current output by the power supply circuit 110 pass through, the high-frequency signals therein will be short-circuited by the capacitor, while the low-frequency signals will pass through the inductor. Therefore, the CL low-pass filter (LC type low-pass filter) can transmit the low-frequency signals to the output end, while the high-frequency signals are shielded.

[0049] Furthermore, since the frequency band range of the electroencephalogram signal is generally 0.5 - 3000 Hz, the low-pass cut-off frequency when the first filtering module and the second filtering module work normally is greater than the frequency band range of the electroencephalogram signal 0.5 - 3000 Hz in order to achieve the purpose of filtering out high-frequency interference signals.

[0050] The parameters of the inductor L101, capacitor C101, inductor L102 and capacitor C102 in the first filtering module and the second filtering module can be determined according to the calculation formula (1) of the cut-off frequency F of the CL type low-pass filter or LC low-pass filter.

[0051]

[0052] Among them, F is the cut-off frequency of the low-pass filter, with the unit of Hz, L is the inductance of the inductor L101 (inductor L102), with the unit of uH, and C is the capacitance of the capacitor C101 (capacitor C102), with the unit of pF.

[0053] In this embodiment, the isolation module adopts a digital isolation chip, and the signal output by the power supply circuit 110 is electrically isolated through the digital isolation chip to protect the backend electroencephalogram acquisition circuit 120 from potential fatal and destructive impacts.

[0054] The digital isolation chip has the advantages of improving signal stability and security, high-speed transmission and low latency, high reliability and long-term stability, low power consumption and high electromagnetic immunity, high integration and cost reduction, and diverse isolation technologies, etc.

[0055] In some embodiments, the isolation module may adopt the RP-0505S high-performance isolation chip produced by Recom Power, which is an isolation module DC converter with excellent performance and high reliability. With its high conversion efficiency, excellent isolation performance, and compact package design, it has been widely used in commercial and medical fields. The isolation voltage of this isolation chip is greater than 5200V, the isolation resistance is greater than 20GΩ, the isolation capacitance is less than or equal to 10pF, with excellent isolation performance and a conversion efficiency of up to 72%, and it supports normal operation within the temperature range of -40°C to 85°C, adapting to various environmental conditions.

[0056] In this embodiment, the output load module includes a parallel connection of resistor R101 and resistor R102. Specifically, the first ends of resistor R101 and resistor R102 are both connected to the output end of the output load module, and the second ends of resistor R101 and resistor R102 are both connected to the preset voltage terminal.

[0057] When the voltage Vin output by the power supply circuit 110 is accompanied by many interference signals, using the power supply isolation circuit 140 provided in the embodiments of the present application, most of the interference signals are absorbed and converted into magnetic induction and heat energy through the inductors in the first filtering module and the second filtering module and the isolation module, and the remaining small part of the interference signals are led out to the ground terminal bypassed by the capacitors in the first filtering module and the second filtering module.

[0058] In summary, the power supply isolation circuit provided in the embodiments of the present application and the anesthesia depth monitor including this power supply isolation circuit, the power supply isolation circuit is connected between the power supply circuit and the EEG acquisition circuit in the anesthesia depth monitor, and the power supply isolation circuit includes an input protection module, a first filtering module, an isolation module, and a second filtering module connected in sequence, filtering and isolating the high-frequency and external interference signals between the power supply circuit and the EEG acquisition circuit through the first filtering module, the isolation module, and the second filtering module, and at the same time being able to cut off the connection between the power supply circuit and the EEG acquisition circuit when the voltage output by the power supply circuit is greater than the preset threshold.

[0059] The present application improves the accuracy of the EEG signals collected by the EEG acquisition circuit through the power supply isolation circuit, can effectively avoid the influence of external signals on the monitoring results of the anesthesia depth monitor, so that the monitoring results are more accurate and reliable, and plays a protective role for both the anesthesia depth monitor and the patient.

[0060] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative rather than restrictive. Under the inspiration of the present application, those of ordinary skill in the art can make several simple deductions, deformations or substitutions without departing from the purpose of the present application and the scope protected by the claims. All of them fall within the protection scope of the present application.

Claims

1. A power isolation circuit is applied to an electroencephalogram (EEG) acquisition device. The EEG acquisition device includes a power circuit and an EEG acquisition circuit, and is characterized in that It includes an input protection module, a first filtering module, an isolation module, and a second filtering module that are connected in sequence; The input end of the input protection module is connected to the output end of the power supply circuit, and the output end of the second filtering module is connected to the input end of the electroencephalogram acquisition circuit; Among them, the input protection module is used to cut off the connection between the power supply circuit and the electroencephalogram acquisition circuit when the voltage output by the power supply circuit is greater than a preset threshold; the first filtering module and the second filtering module are used to filter out high-frequency interference in the voltage output by the power supply circuit; the isolation module is used to isolate the electrical interference signal between the power supply circuit and the electroencephalogram acquisition circuit.

2. The power isolation circuit according to claim 1, characterized in that The input protection module includes a zener diode D101, a zener diode D102, and a fuse F101; The first end of the zener diode D101 is connected to the input end of the input protection module; the first end of the zener diode D102 is connected to the second end of the zener diode D101, and the second end of the zener diode D102 is connected to a preset voltage terminal; the first end of the fuse F101 is connected to the second end of the zener diode D101, and the second end of the fuse F101 is connected to the output end of the input protection module.

3. The power isolation circuit according to claim 1, wherein The first filtering module is a CL type low-pass filter, including an inductor L101 and a capacitor C101; The first end of the inductor L101 is connected to the input end of the first filtering module, and the second end of the inductor L101 is connected to the output end of the first filtering module; the first end of the capacitor C101 is connected to the first end of the inductor L101, and the second end of the capacitor C101 is connected to a preset voltage terminal.

4. The power isolation circuit according to claim 1, characterized in that The second filtering module all adopts an LC low-pass filter, including an inductor L102 and a capacitor C102; The first end of the inductor L102 is connected to the input end of the second filtering module, and the second end of the inductor L102 is connected to the output end of the second filtering module; the first end of the capacitor C102 is connected to the second end of the inductor L102, and the second end of the capacitor C102 is connected to a preset voltage terminal.

5. The power isolation circuit according to claim 1, wherein The low-pass cut-off frequency of the first filtering module and the second filtering module is greater than 3000 Hz.

6. The power isolation circuit according to any one of claims 1-5, characterized in that, The isolation module is a digital isolation chip.

7. The power isolation circuit according to claim 6, wherein The isolation voltage of the isolation module is greater than 5200 V, the isolation resistance is greater than 20 GΩ, and the isolation capacitance is less than or equal to 10 pF.

8. The power isolation circuit according to claim 6, wherein The model of the isolation module is RP-0505S.

9. The power isolation circuit according to claim 1, wherein It also includes an output load module connected between the output end of the second filtering module and the input end of the electroencephalogram acquisition circuit; The output load module includes a resistor R101 and a resistor R102 connected in parallel; among them, the first ends of the resistor R101 and the resistor R102 are both connected to the output end of the output load module, and the second ends of the resistor R101 and the resistor R102 are both connected to a preset voltage terminal.

10. An anesthetic depth monitor, characterized in that, It includes a power supply circuit, an electroencephalogram acquisition circuit, a functional module, and a power supply isolation circuit as described in any one of claims 1-9; The power isolation circuit is connected between the power circuit and the EEG acquisition circuit, and is used to isolate the interference signals between the power circuit and the EEG acquisition circuit.

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