Title :
A 1.1µW 2.1µVRMS input noise chopper-stabilized amplifier for bio-medical applications
Author :
Mandic, Christopher J. ; Gangopadhyay, Daibashish ; Allstot, David J.
Author_Institution :
Dept. of Electr. Eng., Univ. of Washington, Seattle, WA, USA
Abstract :
A low-noise chopper amplifier for bio-signal recording is described. Potential applications include many-electrode implantable ECG acquisition systems along with EEG, EMG and ECoG bio-signals. Designed in 0.13μm CMOS, the two-stage amplifier uses a folded cascode topology with a low-impedance node chopping technique combining both voltage and current-mode chopping for an optimal noise and bias current tradeoff while significantly reducing ripple from the 40 KHz chopper modulation signal. Experimental results show an amplifier with digitally programmable gain from 40 - 83 dB, bandwidth from 340 - 7.5 KHz and high pass cutoff of 170 mHz, while dissipating only 1.1 μW from a 1.2 V supply. The inputreferred noise is 2.1 μVrms integrated over a 100 mHz - 100 KHz bandwidth with a noise efficiency factor of 3.28.
Keywords :
CMOS integrated circuits; amplifiers; biomedical electronics; current-mode circuits; electroencephalography; CMOS; ECoG biosignals; EEG biosignals; EMG biosignals; bandwidth 100 mHz to 100 kHz; bandwidth 340 kHz to 7.5 kHz; biomedical applications; biosignal recording; chopper modulation signal; current-mode chopping; digitally programmable gain; folded cascode topology; frequency 40 kHz; gain 40 dB to 83 dB; input noise chopper-stabilized amplifier; low-impedance node chopping technique; low-noise chopper amplifier; many-electrode implantable ECG acquisition systems; power 1.1 muW; two-stage amplifier; Bandwidth; Choppers (circuits); Gain; Impedance; Mixers; Noise; Topology;
Conference_Titel :
Circuits and Systems (ISCAS), 2012 IEEE International Symposium on
Conference_Location :
Seoul
Print_ISBN :
978-1-4673-0218-0
DOI :
10.1109/ISCAS.2012.6271915
