Electroencephalogram Detection Device, Impedance Detection Method, and Storage Medium

Abstract

The present invention discloses an electroencephalogram detection device, an impedance detection method, and a storage medium. The electroencephalogram detection device includes an impedance network, a switch circuit unit, an analog processing unit, an analog-to-digital conversion unit, and a digital processing unit; a signal output end of the impedance network is electrically connected to a signal input end of the analog processing unit, a driven end of the impedance network is electrically connected to a driving end of the analog processing unit, a signal output end of the analog signal unit is electrically connected to a signal input end of the analog-to-digital conversion unit, a signal output end of the analog-to-digital conversion unit is connected to a signal input end of the digital processing unit, the switch circuit unit is connected in series between the signal output end of the impedance network and the signal input end of the analog processing unit, and a controlled end of the switch circuit unit is electrically connected to a control end of the digital processing unit. Through the present application, the results of the acquisition and processing of electroencephalogram signals can be ensured to be stable and reliable.

Description

Technical Field

[0001] The present invention relates to an electroencephalogram detection device for detecting electroencephalogram signals in the medical field, and particularly to an electroencephalogram detection device, an impedance detection method, and a storage medium. Background Art

[0002] Living human tissue cells always generate very weak bioelectricity. Electroencephalogram signals are the overall effects of the electrical activities of a large number of brain nerve cells in a highly coherent state on the cerebral cortex. By using electrodes placed on the scalp, the electrical activities of brain cells are led out and amplified by an electroencephalogram detection device for analysis and recording. It contains certain waveforms, amplitudes, frequencies, and phases and is variable, which is the electroencephalogram analysis. When the brain tissue undergoes functional changes, this waveform curve will change accordingly, thus providing a basis for clinical diagnosis and treatment.

[0003] Since the electroencephalogram signals themselves are very weak, there are inevitably various external factors during the measurement process that cause artifacts and noise, which affect the quality of the electroencephalogram signals. Interference caused by poor contact between the electrodes and the scalp, power frequency interference, and amplifier channel noise are the three most influential interference sources in electroencephalogram detection. Some traditional electroencephalogram detection devices do not have the function of monitoring the electrode connection status, and some can only partially measure the connection status of the lead electrodes and cannot measure all the lead electrodes. Summary of the Invention

[0004] The present invention provides an electroencephalogram detection device, an impedance detection method, and a storage medium, aiming to solve the technical problem of unstable processing results of electroencephalogram signals.

[0005] To achieve the above object, the present invention provides an electroencephalogram detection device, which includes an impedance network, a switch circuit unit, an analog processing unit, an analog-to-digital conversion unit, and a digital processing unit; the signal output end of the impedance network is electrically connected to the signal input end of the analog processing unit, the driven end of the impedance network is electrically connected to the driving end of the analog processing unit, the signal output end of the analog signal unit is electrically connected to the signal input end of the analog-to-digital conversion unit, the signal output end of the analog-to-digital conversion unit is connected to the signal input end of the digital processing unit, the switch circuit unit is connected in series between the signal output end of the impedance network and the signal input end of the analog processing unit, and the controlled end of the switch circuit unit is electrically connected to the control end of the digital processing unit.

[0006] Further, the electroencephalogram detection device further includes an auxiliary circuit unit, and the auxiliary circuit unit is connected in series between the impedance network and the switch circuit unit.

[0007] Optionally, the electroencephalogram detection device further includes a power supply module, and the power supply module includes a positive power supply, a first resistor, and a second resistor; the positive power supply is a voltage source, one end of the first resistor is connected to the positive power supply, and the other end is connected to the switch circuit unit, one end of the second resistor is connected to the switch circuit unit, and the other end is grounded.

[0008] Further, the digital processing unit includes:

[0009] A switch control sub-unit, electrically connected to the controlled end of the switch circuit unit;

[0010] An impedance detection sub-unit, electrically connected to the signal output end of the analog-to-digital conversion unit, including a test signal filter and an impedance calculator connected to each other;

[0011] An electroencephalogram signal processing sub-unit, electrically connected to the signal output end of the analog-to-digital conversion unit, including an electroencephalogram signal filter and an electroencephalogram signal processor connected to each other.

[0012] Specifically, the analog processing unit includes a filter amplification circuit and a drive circuit, the signal input end of the filter amplification circuit is connected to the signal input end of the impedance network, the signal output end of the filter amplification circuit is connected to the signal input end of the analog-to-digital conversion unit, and the drive end of the drive circuit is connected to the driven end of the impedance network.

[0013] Specifically, the impedance network includes at least two electroencephalogram signal test electrodes, an impedance test auxiliary electrode, and a drive auxiliary electrode. The electroencephalogram signal test electrodes are respectively connected to the signal input end of the filter amplification circuit, the impedance test auxiliary electrode is connected to the signal input end of the filter amplification circuit, and the drive auxiliary electrode is connected to the drive end of the drive circuit.

[0014] Further, the switch circuit unit includes at least two groups of signal test switches and a first switch. The signal test switches correspond to the electroencephalogram signal test electrodes one by one. The signal test switches include a first signal test switch and a second signal test switch. One end of the first signal test switch is connected to the signal output end of the electroencephalogram signal test electrode, the signal input end of the filter amplification circuit, and the node of the second signal test switch. The other end of the first signal test switch is connected to the first resistor; one end of the second signal test switch is connected to the signal output end of the electroencephalogram signal test electrode, the signal input end of the filter amplification circuit, and the node of the first signal test switch. The other end of the second signal test switch is connected to the node of the drive end of the drive circuit and the driven end of the impedance network. One end of the first switch is connected to the second resistor, and the other end of the first switch is connected to the signal input end of the filter amplification circuit.

[0015] To achieve the above object, the present application also proposes an impedance detection method for an electroencephalogram (EEG) detection device. The steps of the impedance detection method for the EEG detection device include:

[0016] Obtain a control instruction and select the working mode of the EEG detection device according to the control instruction;

[0017] If the EEG acquisition mode is selected, acquire an EEG signal and generate an EEG signal processing result according to the EEG signal;

[0018] If the impedance detection mode is selected, obtain a power supply test signal, generate an impedance detection signal according to the power supply test signal, and obtain a theoretical contact impedance based on the impedance detection signal.

[0019] Optionally, obtain the voltage amplitude of the voltage source and the circuit amplification gain;

[0020] Obtain the first resistance value of the first resistor and the second resistance value of the second resistor, and calculate the source fixed resistance value according to the first resistance value and the second resistance value;

[0021] Calculate the theoretical contact impedance according to the voltage amplitude, the source fixed resistance value, the circuit amplification gain, and the impedance detection signal.

[0022] To achieve the above object, the present application also proposes a storage medium. An impedance detection program for an EEG detection device is stored on the storage medium. When the impedance detection program for the EEG detection device is executed by a processor, the EEG detection device is implemented.

[0023] In the present application, an EEG detection device is provided. Since the EEG detection device includes an impedance network, a switch circuit unit, an analog processing unit, an analog-to-digital conversion unit, and a digital processing unit that are connected to each other, the EEG detection device can complete the processing of EEG signals and the detection of the internal impedance of the device, thereby ensuring the stability and reliability of the results of the acquisition and processing of EEG signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0025] Figure 1 It is a schematic diagram of the module structure of an EEG detection device according to an embodiment of the present invention;

[0026] Figure 2Schematic diagram of the module structure of the electroencephalogram detection device according to another embodiment of the present invention;

[0027] Figure 3 Schematic diagram of the module structure of the electroencephalogram detection device according to yet another embodiment of the present invention;

[0028] Figure 4 Schematic diagram of the module structure of the electroencephalogram detection device according to still another embodiment of the present invention;

[0029] Figure 5 Flowchart of the impedance detection method of the electroencephalogram detection device according to an embodiment of the present invention;

[0030] Figure 6 Schematic circuit diagram of the electroencephalogram detection device according to an embodiment of the present invention.

[0031] Explanation of the reference numerals in the drawings:

[0032]

[0033] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the accompanying drawings. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0036] In addition, the descriptions such as "first" and "second" in the present invention are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0037] In the present invention, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" shall be understood in a broad sense. For example, "fixation" may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In addition, the technical solutions between various embodiments of the present invention can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] Based on the above hardware structure, various embodiments of the method of the present invention are proposed.

[0040] Living human tissue cells always generate very weak bioelectricity. The electroencephalogram (EEG) signal is the overall effect of the electrical activities of a large number of brain nerve cells in a highly coherent state on the cerebral cortex. The electrical activities of brain cells are led out by electrodes placed on the scalp and amplified by an EEG detection device for analysis and recording. It has a certain waveform, amplitude, frequency, and phase and is variable, which is the EEG analysis. When the brain tissue undergoes functional changes, this waveform curve will change accordingly, thus providing a basis for clinical diagnosis and treatment.

[0041] Since the EEG signal itself is very weak, various external factors will inevitably cause artifacts and noise during the measurement process, which affect the quality of the EEG signal. The interference caused by poor contact between the electrode and the scalp, power frequency interference, and amplifier channel noise are the three most influential interference sources in EEG detection. Some traditional EEG detection devices do not have the function of monitoring the electrode connection situation, and some can only partially measure the connection situation of the lead electrodes and cannot measure all the lead electrodes.

[0042] To solve the above problems, the present application proposes an EEG detection device, referring to Figure 2, in the first embodiment of the electroencephalogram (EEG) detection device of the present invention, the EEG detection device includes: an impedance network 1, a switch circuit unit 2, an analog processing unit 3, an analog-to-digital conversion unit 4, and a digital processing unit 5; the signal output end of the impedance network 1 is electrically connected to the signal input end of the analog processing unit 3, the driven end of the impedance network 1 is electrically connected to the driving end of the analog processing unit 3, the signal output end of the analog signal unit is electrically connected to the signal input end of the analog-to-digital conversion unit 4, the signal output end of the analog-to-digital conversion unit 4 is connected to the signal input end of the digital processing unit 5, the switch circuit unit 2 is connected in series between the signal output end of the impedance network 1 and the signal input end of the analog processing unit 3, and the controlled end of the switch circuit unit 2 is electrically connected to the control end of the digital processing unit 5.

[0043] In this embodiment, the EEG detection device includes: an impedance network 1, a switch circuit unit 2, an analog processing unit 3, an analog-to-digital conversion unit 4, and a digital processing unit 5. Among them, the impedance network 1 includes at least four lead electrodes for being placed on the scalp to collect the EEG signals of brain cells. The EEG signals are the overall effects of the electrical activities of a large number of brain nerve cells in a highly coherent state on the cerebral cortex.

[0044] The signal output end of the impedance network 1 is electrically connected to the signal input end of the analog processing unit 3. After the impedance network 1 collects the EEG signals, the EEG signals are transmitted to the analog processing unit 3. The analog processing unit 3 is used to perform processing such as filtering and amplifying the EEG signals; in addition, the driving end of the analog processing unit 3 is connected to the driven end of the impedance network 1 for maintaining the traceability of the EEG signals.

[0045] The signal output end of the analog signal unit is electrically connected to the signal input end of the analog-to-digital conversion unit 4. After the EEG signals are filtered and amplified, they enter the analog-to-digital conversion unit 4, and the analog-to-digital conversion unit 4 performs digital quantization and encoding on the EEG signals. In one embodiment, the analog signal unit is a plurality of identical operational amplifiers.

[0046] The signal output end of the analog-to-digital conversion unit 4 is also connected to the signal input end of the digital processing unit 5. The analog-to-digital conversion unit 4 inputs the EEG signals after digital quantization and encoding into the digital processing unit 5, and the digital processing unit 5 can perform signal processing on the EEG signals to obtain the waveform of the electroencephalogram. In one embodiment, the analog-to-digital conversion unit 4 is an AD converter.

[0047] In addition, the switch circuit unit 2 is connected in series between the signal output end of the impedance network 1 and the signal input end of the analog processing unit 3 for controlling the start and stop of the EEG signal detection process.

[0048] The present application provides an electroencephalogram (EEG) detection device. The EEG detection device includes an impedance network 1, a switch circuit unit 2, an analog processing unit 3, an analog-to-digital conversion unit 4, and a digital processing unit 5 that are interconnected. Through the above EEG detection device, the processing of EEG signals and the detection of the internal impedance of the device can be completed, thereby ensuring the stability and reliability of the results of the acquisition and processing of EEG signals.

[0049] In one embodiment, the EEG detection device further includes an auxiliary circuit unit 6, and the auxiliary circuit unit 6 is connected in series between the impedance network 1 and the switch circuit unit 2.

[0050] In this embodiment, the auxiliary circuit unit 6 is connected in series between the impedance network 1 and the switch circuit unit 2. Before the impedance network 1 transmits the acquired EEG signal to the switch circuit unit 2, the EEG signal will first be transmitted to the auxiliary circuit unit 6. The auxiliary circuit unit 6 is used for defibrillation and ESD defibrillation, that is, to limit the harmful large signals in the EEG signal, and then transmit the EEG signal to the switch circuit unit 2.

[0051] In one embodiment, the EEG detection device further includes a power supply module 7. The power supply module 7 includes a positive power supply 71, a first resistor 72, and a second resistor 73. The positive power supply 71 is a voltage source. One end of the first resistor 72 is connected to the positive power supply 71, and the other end is connected to the switch circuit unit 2. One end of the second resistor 73 is connected to the switch circuit unit 2, and the other end is grounded.

[0052] The EEG detection device further includes a power supply module 7. In this embodiment, the power supply module 7 includes a positive power supply 71, a first resistor 72, and a second resistor 73. The positive power supply 71 is a voltage source, and the DC or AC of this voltage source is not limited. If it is AC, the fundamental frequency should be within the band of the analog processing unit 3, and the sine or square wave waveform is not limited. And there is at least one voltage source in the present application.

[0053] In addition, there are two working modes in the EEG detection device of the present application. In the EEG acquisition mode, the voltage source does not work. In addition to the EEG acquisition mode for acquiring and processing EEG signals, there is also an impedance test mode for testing the impedance of the lead electrodes in the impedance network 1. In the impedance test mode, the positive power supply 71 generates a power supply test signal. The power supply test signal can form a closed resistor voltage division network at the scalp through the impedance network 1 to generate an impedance test signal. The impedance test signal sequentially passes through the analog processing unit 3, the analog-to-digital conversion unit 4 and reaches the digital processing unit 5. The digital processing unit 5 can calculate the theoretical contact impedance of each lead electrode according to the impedance test signal.

[0054] In one embodiment, the digital processing unit 5 includes:

[0055] The switch control sub-unit 51 is electrically connected to the controlled end of the switch circuit unit 2;

[0056] The impedance detection sub-unit 52 is electrically connected to the signal output end of the analog-to-digital conversion unit 4, and includes a test signal filter and an impedance calculator connected to each other;

[0057] The electroencephalogram (EEG) signal processing sub-unit 53 is electrically connected to the signal output end of the analog-to-digital conversion unit 4, and includes an EEG signal filter and an EEG signal processor connected to each other.

[0058] In this embodiment, the digital processing unit 5 includes a switch control sub-unit 51, an impedance detection sub-unit 52, and an EEG signal processing sub-unit 53 respectively. Among them, the control end of the switch control sub-unit 51 is electrically connected to the controlled end of the switch circuit unit 2, and is used to control the opening and closing of each switch in the switch circuit unit 2; the signal input end of the impedance detection sub-unit 52 is electrically connected to the signal output end of the analog-to-digital conversion unit 4, and is used to receive the impedance test signal output by the analog-to-digital conversion unit 4, filter out the EEG signal through the test signal filter, and then calculate the theoretical contact impedance of each lead electrode through the impedance calculator.

[0059] The EEG signal processing sub-unit 53 is electrically connected to the signal output end of the analog-to-digital conversion unit 4, and is used to receive the EEG signal output by the analog-to-digital conversion unit 4, filter out the impedance test signal through the EEG signal filter, and then perform final processing on the EEG signal through the EEG signal processor.

[0060] In one embodiment, the analog processing unit 3 includes a filter amplification circuit 31 and a drive circuit 32. The signal input end of the filter amplification circuit 31 is connected to the signal input end of the impedance network 1, the signal output end of the filter amplification circuit 31 is connected to the signal input end of the analog-to-digital conversion unit 4, and the drive end of the drive circuit 32 is connected to the driven end of the impedance network 1.

[0061] In this embodiment, the analog processing unit 3 includes a filter amplification circuit 31 and a drive circuit 32. The signal input end of the filter amplification circuit 31 is connected to the signal output end of the impedance network 1, and the signal output end of the filter amplification circuit 31 is connected to the signal input end of the analog-to-digital conversion unit 4, and is used to filter and amplify the impedance test signal and the EEG signal. The drive end of the drive circuit 32 is connected to the driven end of the impedance network 1. Whether in the EEG acquisition mode or the impedance test mode, the drive circuit 32 can extract the slow-changing wave in the EEG signal, and pass the slow-changing wave through the impedance module to reach the user's scalp, and negatively feedback to the scalp to cancel the static voltage fluctuation on the scalp, so as to compress the dynamic range of the EEG signal to match the signal input range of the analog processing unit 3, so as to maintain the traceability of the EEG signal.

[0062] In one embodiment, the impedance network 1 includes at least two electroencephalogram (EEG) signal test electrodes Z1-Zn, an impedance test auxiliary electrode Zref, and a drive auxiliary electrode Zgnd. The EEG signal test electrodes Z1-Zn are respectively connected to the signal input ends of the filtering and amplifying circuit 31. The impedance test auxiliary electrode Zref is connected to the signal input end of the filtering and amplifying circuit 31. The drive auxiliary electrode Zgnd is connected to the drive end of the drive circuit 32.

[0063] In this embodiment, the impedance network 1 includes at least two EEG signal test electrodes Z1-Zn, at least one impedance test auxiliary electrode Zref, and at least one drive auxiliary electrode Zgnd. The EEG signal test electrodes Z1-Zn are respectively connected to the signal input ends of the filtering and amplifying circuit 31. The impedance test auxiliary electrode Zref is connected to the signal input end of the filtering and amplifying circuit 31. The drive auxiliary electrode Zgnd is connected to the drive end of the drive circuit 32. Among them, the EEG signal test electrodes Z1-Zn are used to collect EEG signals. The impedance test auxiliary electrode Zref is used for impedance testing. The drive auxiliary electrode Zgnd is used to assist the drive circuit 32 to maintain the traceability of the EEG signals.

[0064] In one embodiment, the switch circuit unit 2 includes at least two groups of signal test switches and a first switch S0. The signal test switches correspond to the EEG signal test electrodes Z1-Zn one by one. The signal test switch includes a first signal test switch S1 and a second signal test switch S2. One end of the first signal test switch S1 is connected to the signal output end of the EEG signal test electrode Z1-Zn, the signal input end of the filtering and amplifying circuit 31, and the node of the second signal test switch S2. The other end of the first signal test switch S1 is connected to the first resistor 72. One end of the second signal test switch S2 is connected to the signal output end of the EEG signal test electrode Z1-Zn, the signal input end of the filtering and amplifying circuit 31, and the node of the first signal test switch S1. The other end of the second signal test switch S2 is connected to the node of the drive end of the drive circuit 32 and the driven end of the impedance network 1. One end of the first switch S0 is connected to the second resistor 73. The other end of the first switch S0 is connected to the signal input end of the filtering and amplifying circuit 31.

[0065] In this embodiment, as Figure 6 shown, the switch circuit unit 2 includes at least two groups of signal test switches. Each group of signal test switches includes two, and each group of signal test switches corresponds to an EEG signal test electrode Z1-Zn one by one. Specifically, each signal test switch can control whether the power test signal passes through the impedance network 1 to form a closed loop at the scalp, generating an impedance test signal.

[0066] Furthermore, the filtering and amplifying circuit 31 includes at least three operational amplifiers, including two electroencephalogram (EEG) signal testing operational amplifiers and one driving auxiliary operational amplifier. The EEG signal testing electrodes Z1-Zn correspond one-to-one with the EEG signal testing operational amplifiers, and the driving auxiliary electrode Zgnd corresponds to the driving auxiliary operational amplifier. Specifically, each of the EEG signal testing electrodes Z1-Zn is connected to the non-inverting input terminal of its corresponding EEG signal testing operational amplifier, the driving auxiliary electrode Zgnd is connected to the non-inverting input terminal of the driving auxiliary operational amplifier, and the impedance testing auxiliary electrode Zref is connected to the inverting input terminals of all operational amplifiers.

[0067] The present invention also provides an impedance detection method for an EEG detection device. The steps of the impedance detection method for the EEG detection device include:

[0068] Step S100, obtaining a control instruction and selecting the working mode of the EEG detection device according to the control instruction;

[0069] Step S200, if the EEG acquisition mode is selected, acquiring an EEG signal and generating an EEG signal processing result according to the EEG signal;

[0070] Step S300, if the impedance detection mode is selected, obtaining a power supply test signal, generating an impedance detection signal according to the power supply test signal, and obtaining a theoretical contact impedance based on the impedance detection signal.

[0071] There are two working modes in the EEG detection device of the present application. One working mode is the EEG acquisition mode for acquiring and processing EEG signals, and the other working mode is the impedance test mode for testing the impedance of the lead electrodes in the impedance network 1.

[0072] In the EEG acquisition mode, at least two EEG signal testing electrodes Z1-Zn in the impedance network 1 are placed on the user's scalp and respectively acquire the EEG signals on the human scalp. The EEG signals can reach the switch circuit unit 2 and the auxiliary circuit unit 6 simultaneously. In the EEG acquisition mode, all switches in the switch circuit unit 2 are disconnected. Therefore, the power supply module 7 will not affect the EEG acquisition, and the auxiliary circuit unit 6 limits the harmful large signals in the EEG signals. Then the EEG signals enter the analog processing unit 3. The analog processing unit 3 filters and amplifies the EEG signals. The amplified EEG signals enter the analog-to-digital conversion unit 4 to be converted from analog signals to digital signals. The converted EEG signals enter the digital processing unit 5 to obtain the EEG signal processing result. Among them, the EEG signal processing result can be an electroencephalogram in the form of a curve graph or a record in the form of text.

[0073] In the impedance test mode, the positive power supply 71 generates a power supply test signal. As Figure 6 shown, in the impedance test mode, the switch S0 is closed, and in the switch circuit unit 2, S1 - Sn are closed in turn for a first preset duration and then opened, so as to test the theoretical contact impedance of each EEG signal test electrode Z1 - Zn in the impedance network 1 in turn. Herein, the first preset duration is a time length set in advance by those skilled in the art. In this way, the power supply test signal passes through the impedance network 1 and will form a closed loop at the scalp, generating an impedance test signal for the analog processing unit 3. The analog processing unit 3 will also filter and amplify the impedance test signal. Then, the impedance test signal reaches the digital processing unit 5 through the analog-to-digital conversion unit 4. The digital processing unit 5 can calculate the theoretical contact impedance of each lead electrode according to the impedance test signal.

[0074] In one embodiment, the step of obtaining the theoretical contact impedance based on the impedance detection signal includes:

[0075] Obtaining the voltage amplitude of the voltage source and the circuit amplification gain;

[0076] Obtaining the first resistance value of the first resistor 72 and the second resistance value of the second resistor 73, and calculating the source fixed resistance value according to the first resistance value and the second resistance value;

[0077] Calculating the theoretical contact impedance according to the voltage amplitude, the source fixed resistance value, the circuit amplification gain, and the impedance detection signal.

[0078] In this embodiment, taking Figure 6 as an example, since the positive power supply 71 is a voltage source, the voltage amplitude of the voltage source can be set as U. Then, the amplitudes of the impedance detection signals received in the digital processing unit 5 can be U1, U2......U n-1 , U n , U 1g , U 2g , and the first resistance value of the first resistor 72 can be set as R0, and the second resistance value of the second resistor 73 can be set as R1. Therefore, since the first resistor 72 and the second resistor 73 are in series, the resistance value of the source fixed resistor can be calculated as the sum of the first resistance value and the second resistance value. The source fixed resistor R exists:

[0079] R = R0 + R1

[0080] Among them, U 1g is the signal amplitude of the impedance detection signal passing through the CH1 channel after the switch S1 is closed; U 2g is the signal amplitude of the impedance detection signal passing through the CH2 channel after the switch S2 is closed. Then, the following equations can be listed:

[0081]

[0082] Among them, Z1, Z2, Z3.......Z n , Z ref , Z gnd are the theoretical contact impedances corresponding to the respective lead electrodes. g is the circuit amplification gain of the analog processing unit 3. When I, g, R, U1, U2......U n-1 , U n , U 1g , U 2g are all known quantities, the theoretical contact impedances of the respective lead electrodes can be calculated. Based on the above calculation method, the present application supports contact impedance testing for zero electrodes, and the present application supports impedance testing for lead electrodes of a fully differential circuit.

[0083] The present invention also proposes a storage medium, on which an impedance detection program of an electroencephalogram detection device is stored. The storage medium includes a computer-readable storage medium, and the computer-readable storage medium can be Figure 1 the memory in, or at least one of ROM (Read-Only Memory), RAM (Random Access Memory), magnetic disk, and optical disc. The storage medium includes several instructions for causing an Internet of Things terminal device having a processor (which can be a mobile phone, a computer, a server, an Internet of Things terminal, or a network device, etc.) to execute the methods described in various embodiments of the present invention.

[0084] In the present invention, the terms "first", "second", "third", "fourth", and "fifth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0085] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in multiple embodiments or examples of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0086] Although the embodiments of the present invention have been shown and described above, the scope of protection of the present invention is not limited thereto. It can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, and substitutions to the above embodiments within the scope of the present invention, and these changes, modifications, and substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. An electroencephalogram detection device, characterized in that, The electroencephalogram (EEG) detection device includes an impedance network, a switch circuit unit, an analog processing unit, an analog-to-digital conversion unit, and a digital processing unit; the signal output end of the impedance network is electrically connected to the signal input end of the analog processing unit, the driven end of the impedance network is electrically connected to the driving end of the analog processing unit, the signal output end of the analog processing unit is electrically connected to the signal input end of the analog-to-digital conversion unit, the signal output end of the analog-to-digital conversion unit is connected to the signal input end of the digital processing unit, the switch circuit unit is connected in series between the signal output end of the impedance network and the signal input end of the analog processing unit, and the controlled end of the switch circuit unit is electrically connected to the control end of the digital processing unit. Among them, the analog processing unit includes a filter amplification circuit and a driving circuit, the signal input end of the filter amplification circuit is connected to the signal input end of the impedance network, the signal output end of the filter amplification circuit is connected to the signal input end of the analog-to-digital conversion unit, and the driving end of the driving circuit is connected to the driven end of the impedance network.

2. The electroencephalogram detection device according to claim 1, characterized in that, The EEG detection device further includes an auxiliary circuit unit, which is connected in series between the impedance network and the switch circuit unit.

3. The electroencephalogram detection device according to claim 1, wherein, The EEG detection device further includes a power supply module, which includes a positive power supply, a first resistor, and a second resistor; the positive power supply is a voltage source, one end of the first resistor is connected to the positive power supply, the other end is connected to the switch circuit unit, one end of the second resistor is connected to the switch circuit unit, and the other end is grounded.

4. The electroencephalogram detection device according to claim 3, characterized in that, The digital processing unit includes: a switch control sub-unit, which is electrically connected to the controlled end of the switch circuit unit; an impedance detection sub-unit, which is electrically connected to the signal output end of the analog-to-digital conversion unit and includes a test signal filter and an impedance calculator connected to each other; an EEG signal processing sub-unit, which is electrically connected to the signal output end of the analog-to-digital conversion unit and includes an EEG signal filter and an EEG signal processor connected to each other.

5. The electroencephalogram detection device according to claim 3, characterized in that The impedance network includes at least two EEG signal test electrodes, an impedance test auxiliary electrode, and a driving auxiliary electrode. The EEG signal test electrodes are respectively connected to the signal input end of the filter amplification circuit, the impedance test auxiliary electrode is connected to the signal input end of the filter amplification circuit, and the driving auxiliary electrode is connected to the driving end of the driving circuit.

6. The EEG detection device according to claim 5, characterized in that, The switch circuit unit includes at least two groups of signal test switches and a first switch. The signal test switches correspond to the EEG signal test electrodes one by one. The signal test switches include a first signal test switch and a second signal test switch. One end of the first signal test switch is connected to the signal output end of the EEG signal test electrode, the signal input end of the filter amplification circuit, and the node of the second signal test switch. The other end of the first signal test switch is connected to the first resistor. One end of the second signal test switch is connected to the signal output end of the EEG signal test electrode, the signal input end of the filter amplification circuit, and the node of the first signal test switch. The other end of the second signal test switch is connected to the node of the driving end of the driving circuit and the driven end of the impedance network. One end of the first switch is connected to the second resistor, and the other end of the first switch is connected to the signal input end of the filter amplification circuit.

7. An impedance detection method for an electroencephalogram detection device according to any one of claims 1 to 6, characterized in that, The steps of the impedance detection method of the EEG detection device include: Obtain a control instruction and select the working mode of the EEG detection device according to the control instruction; If the EEG acquisition mode is selected, acquire the EEG signal and generate an EEG signal processing result according to the EEG signal; If the impedance detection mode is selected, obtain a power supply test signal, generate an impedance detection signal according to the power supply test signal, and obtain a theoretical contact impedance based on the impedance detection signal.

8. The impedance detection method of the electroencephalogram detection device according to claim 7, characterized in that The step of obtaining the theoretical contact impedance based on the impedance detection signal includes: Obtain the voltage amplitude of the voltage source and the circuit amplification gain; Obtain the first resistance value of the first resistor and the second resistance value of the second resistor, and calculate the source fixed resistance value according to the first resistance value and the second resistance value; Calculate the theoretical contact impedance according to the voltage amplitude, the source fixed resistance value, the circuit amplification gain, and the impedance detection signal.

9. A storage medium, characterized in that, An impedance detection program of the EEG detection device is stored on the storage medium. When the impedance detection program of the EEG detection device is executed by a processor, the steps of the EEG detection device described in any one of claims 7 to 8 are implemented.

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