2012 · 15 citations · 12 references
Medical ElectronicsEngineeringWearable TechnologyBiomedical EngineeringWireless Implantable DeviceMedical InstrumentationElectrophysiological EvaluationBioimpedance SensorsBiosensing SystemsBiomedical DevicesInstrumentationDry ElectrodesElectrical EngineeringImplantable SensorComputer EngineeringBioinstrumentationEcg SystemBiomedical SensorsPhysiologyBioelectronicsBiomedical InstrumentationElectrophysiologyCopper Electrodes
A wireless 8-channel biopotential acquisition system for capturing electrocardiogram (ECG) using dry electrodes is presented. The ECG system consists of copper electrodes, a micropowered 8-channel custom ASIC, and an off-the-shelf microprocessor and bluetooth radio. Each analog channel of the custom ECG front-end is composed of a chopper-modulated instrumentation amplifier (CMIA) with chopping spike filter (CSF), a programmable gain amplifier (PGA), and a output buffer. Implemented in standard a 0.35 μm CMOS technology, the ECG front-end consumes 101 μA from a 2.7 V supply, occupying 5 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> of chip area. Measurement results show an input impedance of 1 G Ω, an input-referred noise of 0.97 μVrms (0.5 ~ 100 Hz), and a CMRR of 114 dB. Finally, a complete wireless 8-channel ECG monitoring system incorporating this analog front-end is demonstrated, showing successful recordings of a capture ECG waveform using a smart phone.
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