针对脑电检测的研究需要,研发了微弱EEG脑电信号采集专用芯片系统。该芯片使用斩波稳定去噪声技术,首先利用2 k Hz的斩波频率对100 Hz以下的EEG信号进行频域隔离,然后利用RRL纹波抑制环路反馈进行调制后位于chopper频率处的主要由失调...针对脑电检测的研究需要,研发了微弱EEG脑电信号采集专用芯片系统。该芯片使用斩波稳定去噪声技术,首先利用2 k Hz的斩波频率对100 Hz以下的EEG信号进行频域隔离,然后利用RRL纹波抑制环路反馈进行调制后位于chopper频率处的主要由失调与低频1/f闪烁噪声引起的纹波电压的抑制;单级斩波放大使用电流复用、亚阈值跨导增强技术对来自EEG传感器的低频（〈100 Hz）小信号（5~100μV）进行40 d B增益的稳定中频放大;级联S/H电路进行去累积毛刺滤波,配合前面斩波技术,达到整体低噪声性能;VGA/LPF通过改变输入、反馈/负载电容,分别进行增益/带宽的数字调整。EEG-DSP加速芯片实现对多通道采集的控制以及信号处理编码。设计使用SMICRF 180 nm混合工艺,使用Cadence的Spectre软件进行功能前/后仿真,使用Caliber工具进行DRC/LVS的版图验收。最后,对设计芯片进行实际测试,结果表明放大芯片关键性能为：8.1μW/通道、面积6.3 mm2/8通道、0.8μVrms（BW=100 Hz）等效输入噪声;该款自主研发的脑电斩波放大芯片性能达到国内外前列的水平,可进行正确的脑电EEG采集,可应用于可穿戴领域、对后续脑电数据分析具有重要的使用价值。展开更多
Facing the body＇s EEG（electroencephalograph, 0.5–100 Hz, 5–100 μV） and ECG＇s（electrocardiogram,〈 100 Hz, 0.01–5 mV） micro signal detection requirement, this paper develops a pervasive application micro sign...Facing the body＇s EEG（electroencephalograph, 0.5–100 Hz, 5–100 μV） and ECG＇s（electrocardiogram,〈 100 Hz, 0.01–5 mV） micro signal detection requirement, this paper develops a pervasive application micro signal detection ASIC chip with the chopping modulation/demodulation method. The chopper-stabilization circuit with the RRL（ripple reduction loop） circuit is to suppress the ripple voltage, which locates at the single-stage amplifier＇s outputting terminal. The single-stage chopping core＇s noise has been suppressed too, and it is beneficial for suppressing noises of post-circuit. The chopping core circuit uses the PFB（positive feedback loop） to increase the inputting resistance, and the NFB（negative feedback loop） to stabilize the 40 dB intermediate frequency gain. The cascaded switch-capacitor sample/hold circuit has been used for deleting spike noises caused by non-ideal MOS switches, and the VGA/BPF（voltage gain amplifier/band pass filter） circuit is used to tune the chopper system＇s gain/bandwidth digitally. Assisted with the designed novel dry-electrode, the real test result of the chopping amplifying circuit gives some critical parameters： 8.1 μW/channel, 0.8 μVrms（@band-widthD100 Hz）, 4216–11220 times digitally tuning gain range, etc. The data capture system uses the NI CO＇s data capturing DAQmx interface,and the captured micro EEG/ECG＇s waves are real-time displayed with the PC-Labview. The proposed chopper system is a unified EEG/ECG signal＇s detection instrument and has a critical real application value.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.61527815,31500800,61501426,61471342)the National Key Basic Research Plan(No.2014CB744600)+1 种基金the Beijing Science and Technology Plan(No.Z141100000214002)the Chinese Academy of Sciences’Key Project(No.KJZD-EW-L11-2)
文摘Facing the body＇s EEG（electroencephalograph, 0.5–100 Hz, 5–100 μV） and ECG＇s（electrocardiogram,〈 100 Hz, 0.01–5 mV） micro signal detection requirement, this paper develops a pervasive application micro signal detection ASIC chip with the chopping modulation/demodulation method. The chopper-stabilization circuit with the RRL（ripple reduction loop） circuit is to suppress the ripple voltage, which locates at the single-stage amplifier＇s outputting terminal. The single-stage chopping core＇s noise has been suppressed too, and it is beneficial for suppressing noises of post-circuit. The chopping core circuit uses the PFB（positive feedback loop） to increase the inputting resistance, and the NFB（negative feedback loop） to stabilize the 40 dB intermediate frequency gain. The cascaded switch-capacitor sample/hold circuit has been used for deleting spike noises caused by non-ideal MOS switches, and the VGA/BPF（voltage gain amplifier/band pass filter） circuit is used to tune the chopper system＇s gain/bandwidth digitally. Assisted with the designed novel dry-electrode, the real test result of the chopping amplifying circuit gives some critical parameters： 8.1 μW/channel, 0.8 μVrms（@band-widthD100 Hz）, 4216–11220 times digitally tuning gain range, etc. The data capture system uses the NI CO＇s data capturing DAQmx interface,and the captured micro EEG/ECG＇s waves are real-time displayed with the PC-Labview. The proposed chopper system is a unified EEG/ECG signal＇s detection instrument and has a critical real application value.
