A low power configurable bio-impedance spectroscopy (BIS) ASIC with simultaneous ECG and respiration recording functionality

This paper presents a power-efficient ASIC for bio-impedance spectroscopy, as well as ECG and respiration recording. The ASIC includes a wideband stimulation current source with a pseudo-random binary sequence, a low-noise instrumentation amplifier, and a low power 12b SAR ADC. This ASIC is able to measure bio-impedances from 1Ω to 10kΩ with 0.1Ω resolution, and covers a frequency range up to 125kHz. Furthermore, the ASIC can simultaneously record ECG and respiration while consuming only 31μW from a 1.8V supply.