Table 1.

Specifications of sensor's amplifier and filter.

Part name	Character	Gain
Pre-amplifier (Instrument Amplifier)	Differential input impendence: 10 Gohm‖2 pF; CMRR: 120 dB; Input bias current: 1 nA; Input offset voltage: 25 μV	ECG: 20 dB PPG: 20 dB Respiration: 20 dB
High Pass Filter (LPF)	2nd-order Butterworth filter Cutoff frequency: ECG, 0.5 Hz; PPG, 0.1 Hz; Respiration: 0.1 Hz	0 dB
Low Pass Filter (HPF)	5th-order Bessel filter Cutoff frequency: ECG, 40 Hz; PPG, 20 Hz; Respiration: 10 Hz	0 dB
2rd Amplifier	Invert Amplifier	ECG:40 dB PPG: 20 dB Respiration:10 dB
Notch Filter	60 Hz Twin-T notch filter	0 dB