阅读说明：本技术 一种多选择参考电极的eeg信号采集前端电路 (EEG signal acquisition front-end circuit of multi-selection reference electrode ) 是由 白帆 卢树强 王晓岸 于 2021-08-13 设计创作，主要内容包括：本申请公开了一种多选择参考电极的EEG信号采集前端电路,包括：第一通道参考电极、第二通道参考电极、第三通道参考电极、第四通道参考电极、公共参考电极、第一通道测量电极、第二通道测量电极、第三通道测量电极、第四通道测量电极；与所述第一通道参考电极、第二通道参考电极、第三通道参考电极、第四通道参考电极、公共参考电极相连的可编程控制开关；第一信号采集电路,第二信号采集电路,第三信号采集电路,第四信号采集电路。可见,该EEG信号采集前端电路实现保证各个通道间数据采样的独立性,不会受到其他通道干扰。(The application discloses EEG signal acquisition front-end circuit of many options reference electrode includes: the device comprises a first channel reference electrode, a second channel reference electrode, a third channel reference electrode, a fourth channel reference electrode, a common reference electrode, a first channel measuring electrode, a second channel measuring electrode, a third channel measuring electrode and a fourth channel measuring electrode; the programmable control switch is connected with the first channel reference electrode, the second channel reference electrode, the third channel reference electrode, the fourth channel reference electrode and the common reference electrode; the signal acquisition device comprises a first signal acquisition circuit, a second signal acquisition circuit, a third signal acquisition circuit and a fourth signal acquisition circuit. Therefore, the EEG signal acquisition front-end circuit can ensure the independence of data sampling among channels and cannot be interfered by other channels.)

1. A multi-selection reference electrode EEG signal acquisition front-end circuit comprising:

the device comprises a first channel reference electrode, a second channel reference electrode, a third channel reference electrode, a fourth channel reference electrode, a common reference electrode, a first channel measuring electrode, a second channel measuring electrode, a third channel measuring electrode and a fourth channel measuring electrode;

the programmable control switch is connected with the first channel reference electrode, the second channel reference electrode, the third channel reference electrode, the fourth channel reference electrode and the common reference electrode;

the device comprises a programmable control switch, a first signal acquisition circuit connected with the programmable control switch and a first channel measuring electrode, a second signal acquisition circuit connected with the programmable control switch and a second channel measuring electrode, a third signal acquisition circuit connected with the programmable control switch and a third channel measuring electrode, and a fourth signal acquisition circuit connected with the programmable control switch and a fourth channel measuring electrode.

2. The EEG signal acquisition front-end circuit of claim 1, wherein said programmable control switch is a four-bank, two-out switch having eight inputs and four outputs.

3. The EEG signal acquisition front-end circuit according to claim 2, wherein said first channel reference electrode is connected to a first input of a programmable control switch, wherein said second channel reference electrode is connected to a third input of the programmable control switch, wherein said third channel reference electrode is connected to a fifth input of the programmable control switch, and wherein said fourth channel reference electrode is connected to a seventh input of the programmable control switch.

4. The EEG signal acquisition front-end circuit according to claim 3, wherein said common reference electrode is connected to a second input, a fourth input, a sixth input, an eighth input of a programmable control switch.

5. The EEG signal acquisition front-end circuit of claim 2, wherein said programmable control switch is an ADG1634 chip.

6. The EEG signal acquisition front-end circuit of claim 1, further comprising:

4(N-1) measuring electrodes, 4(N-1) reference electrodes and 4(N-1) signal acquisition circuits, wherein N is more than or equal to 2 and is a positive integer;

the programmable control switch is 4N groups of alternative switches and is provided with 8N input ends and 4N output ends; each group of input of the programmable control switch is provided with two input ends which are respectively connected with a common reference electrode and a reference electrode of one channel;

the EEG signal acquisition front-end circuit is used for acquiring EEG signal data of 4N channels.

Technical Field

The present application relates to the field of signal acquisition technologies, and in particular, to an EEG signal acquisition front-end circuit for a multiple-selection reference electrode.

Background

Existing EEG signal acquisition systems are only equipped with one common reference electrode for any number of channels. This has the problem that the common reference electrode causes cross talk between the channels. For example, if only the first channel operates, and other channels cannot actually and normally operate due to poor contact, other channels may generate corresponding waveforms due to interference of the common reference electrode, and the waveforms may not be determined whether the waveforms are waveforms generated by real data or waveforms caused by crosstalk.

Therefore, how to ensure the independence of data sampling among the channels is an urgent problem to be solved without being interfered by other channels.

Disclosure of Invention

The application aims to provide an EEG signal acquisition front-end circuit of a multi-selection reference electrode, which can ensure the independence of data sampling among channels and cannot be interfered by other channels.

To solve the above technical problem, the present application provides an EEG signal acquisition front-end circuit with multiple selective reference electrodes, comprising:

the device comprises a first channel reference electrode, a second channel reference electrode, a third channel reference electrode, a fourth channel reference electrode, a common reference electrode, a first channel measuring electrode, a second channel measuring electrode, a third channel measuring electrode and a fourth channel measuring electrode;

the programmable control switch is connected with the first channel reference electrode, the second channel reference electrode, the third channel reference electrode, the fourth channel reference electrode and the common reference electrode;

the device comprises a programmable control switch, a first signal acquisition circuit connected with the programmable control switch and a first channel measuring electrode, a second signal acquisition circuit connected with the programmable control switch and a second channel measuring electrode, a third signal acquisition circuit connected with the programmable control switch and a third channel measuring electrode, and a fourth signal acquisition circuit connected with the programmable control switch and a fourth channel measuring electrode.

Preferably, the programmable control switch is a four-group two-to-one switch, and has eight input ends and four output ends.

Preferably, the first channel reference electrode is connected to the first input terminal of the programmable control switch, the second channel reference electrode is connected to the third input terminal of the programmable control switch, the third channel reference electrode is connected to the fifth input terminal of the programmable control switch, and the fourth channel reference electrode is connected to the seventh input terminal of the programmable control switch.

Preferably, the common reference electrode is connected to the second input terminal, the fourth input terminal, the sixth input terminal and the eighth input terminal of the programmable control switch.

Preferably, the programmable control switch is an ADG1634 chip.

Preferably, the EEG signal acquisition front-end circuit further comprises:

4(N-1) measuring electrodes, 4(N-1) reference electrodes and 4(N-1) signal acquisition circuits, wherein N is more than or equal to 2 and is a positive integer;

the programmable control switch is 4N groups of alternative switches and is provided with 8N input ends and 4N output ends; each group of input of the programmable control switch is provided with two input ends which are respectively connected with a common reference electrode and a reference electrode of one channel;

the EEG signal acquisition front-end circuit is used for acquiring EEG signal data of 4N channels.

The application provides an EEG signal acquisition front-end circuit of many options reference electrode, has two kinds of schemes to select to the reference electrode: 1. each channel is provided with a separate reference electrode; 2. the circuit is also provided with a common reference electrode. Therefore, reliable switch switching is realized, a user selects to use the independent reference electrode or the common reference electrode according to requirements, the independent reference electrode of each channel is used, the data acquisition independence among the channels is guaranteed, the interference of other channels cannot be received, and the waveform of the output waveform of the channel is guaranteed.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an EEG signal acquisition front-end circuit of a multiple-selection reference electrode according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of an EEG signal acquisition front-end circuit of another multiple-selection reference electrode according to an embodiment of the present application.

Detailed Description

The core of the application is to provide an EEG signal acquisition front-end circuit of a multi-selection reference electrode, so that the independence of data sampling among channels is guaranteed, and the EEG signal acquisition front-end circuit cannot be interfered by other channels.

In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an EEG signal acquisition front-end circuit with multiple reference electrodes according to an embodiment of the present disclosure, the EEG signal acquisition front-end circuit includes:

a first channel reference electrode 11, a second channel reference electrode 12, a third channel reference electrode 13, a fourth channel reference electrode 14, a common reference electrode 15, a first channel measuring electrode 21, a second channel measuring electrode 22, a third channel measuring electrode 23 and a fourth channel measuring electrode 24;

a programmable control switch 16 connected with the first channel reference electrode 11, the second channel reference electrode 12, the third channel reference electrode 13, the fourth channel reference electrode 14 and the common reference electrode 15;

a first signal acquisition circuit 31 connected with the programmable control switch 16 and the first channel measuring electrode 21, a second signal acquisition circuit 32 connected with the programmable control switch 16 and the second channel measuring electrode 22, a third signal acquisition circuit 33 connected with the programmable control switch 16 and the third channel measuring electrode 23, and a fourth signal acquisition circuit 34 connected with the programmable control switch 16 and the fourth channel measuring electrode 24.

The EEG signal acquisition front-end circuit comprises 4 channel measurement electrodes and a reference electrode, wherein electrode P represents a measurement electrode positive input, namely a measurement electrode, and electrode N represents a reference electrode negative input, namely a reference electrode. Channel 1 represents a first Channel, Channel 2 represents a second Channel, Channel3 represents a third Channel, and Channel4 represents a fourth Channel. Electrode N (channel 1) represents a first channel reference Electrode, Electrode P (channel 1) represents a first channel measurement Electrode, Electrode N (channel 2) represents a second channel reference Electrode, Electrode P (channel 2) represents a second channel measurement Electrode, Electrode N (channel3) represents a third channel reference Electrode, Electrode P (channel3) represents a third channel measurement Electrode, Electrode N (channel4) represents a fourth channel reference Electrode, and Electrode P (channel4) represents a fourth channel measurement Electrode. The common reference denotes a common reference electrode. Mux (2:1) × 4 denotes a programmable control switch, specifically, four sets of one-out-of-two switches, abbreviated as Mux.

In the present application, there are two options for the reference electrode: 1. each channel is provided with a separate reference electrode; 2. the circuit is also provided with a common reference electrode. Therefore, reliable switch switching is realized, a user selects to use the independent reference electrode or the common reference electrode according to requirements, the independent reference electrode of each channel is used, the data acquisition independence among the channels is guaranteed, the interference of other channels cannot be received, and the waveform of the output waveform of the channel is guaranteed.

The programmable control switch is four groups of two-to-one switches and is provided with eight input ends and four output ends. The first channel reference electrode is connected with the first input end of the programmable control switch, the second channel reference electrode is connected with the third input end of the programmable control switch, the third channel reference electrode is connected with the fifth input end of the programmable control switch, and the fourth channel reference electrode is connected with the seventh input end of the programmable control switch. And the common reference electrode is connected with the second input end, the fourth input end, the sixth input end and the eighth input end of the programmable control switch.

In detail, the programmable control switch is an ADG1634 chip. The signal acquisition circuit can comprise an instrument amplifier, a high-pass filter, a low-pass filter and the like, is a signal acquisition circuit commonly used in the prior art and can be determined according to specific requirements, and the part is not important for the application. Referring to fig. 2, fig. 2 is a schematic structural diagram of an EEG signal acquisition front end circuit with multiple selective reference electrodes according to an embodiment of the present disclosure, where the signal acquisition circuit includes an instrumentation amplifier, and other elements in the signal acquisition circuit are not shown in the figure except the instrumentation amplifier, an electrode P enters an anode of the instrumentation amplifier, a reference electrode enters a cathode of the instrumentation amplifier, and then filtering, amplifying, and other EEG signal acquisition operations are performed.

Based on this application, it is further that EEG signal acquisition front-end circuit still includes: 4(N-1) measuring electrodes, 4(N-1) reference electrodes and 4(N-1) signal acquisition circuits, wherein N is more than or equal to 2 and is a positive integer; the programmable control switch is 4N groups of alternative switches and is provided with 8N input ends and 4N output ends; each group of input of the programmable control switch is provided with two input ends which are respectively connected with a common reference electrode and a reference electrode of one channel; the EEG signal acquisition front-end circuit is used for acquiring EEG signal data of 4N channels. The EEG signal acquisition front-end circuit can detect more channels such as 8 channels, 16 channels, 32 channels and the like.

The 4 channels are shown in fig. 1, and detection of 8, 16, 32 and more channels can be actually performed according to needs. An ADG1634 chip can be used as a programmable control switch to control the switching of the switch, each group of inputs are respectively an independent reference electrode and a common reference electrode of a channel, and the switch is programmed and switched by an MCU to select one output. For example: the electrode N and the common reference of the Channel 1 are connected into the 1-out-of-2 switch of one group of the MUXs, and the electrode N or the common reference of the Channel 1 is selected and output according to logic control. The selected electrode enters the instrumentation amplifier together with the measuring electrode of the corresponding channel, the electrode P enters the anode of the instrumentation amplifier, and the reference electrode enters the cathode of the instrumentation amplifier. Then, EEG signal acquisition operations such as filtering, amplification and the like are carried out.

The application provides two selection schemes for users: 1. by using the reference electrode of each channel, the scheme ensures the independence of data acquisition among the channels, does not receive the interference of other channels, and ensures that the output waveform is the waveform of the channel. 2. The common reference electrode is used, in a circuit equipped with a real-time impedance test, the signal acquisition quality of each channel can be ensured due to the real-time impedance test, under the condition that all channels are in good contact, the influence of channel crosstalk on an output waveform is small, and one common electrode can be used as the reference electrode of the circuit, so that the number of electrode wearing and the complexity of structural design are reduced.

Different reference electrodes can be switched according to requirements, and a common reference electrode or a reference electrode with each channel being independent is used, so that signal acquisition is more accurate.

The EEG signal acquisition front-end circuit for a multiple selection reference electrode provided by the present application is described in detail above. The principles and embodiments of the present application are explained herein using specific examples, which are provided only to help understand the method and the core idea of the present application. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present application without departing from the principle of the present application, and such improvements and modifications also fall within the scope of the claims of the present application.