An ultra-low power interface CMOS IC design for biosensor applications

This paper presents a design example of an ultra-low power single-channel analog front-end (AFE) integrated circuits (IC) and system for biomedical sensing applications. The 0.18-μm CMOS AFE IC design includes a low noise instrumentation amplifier (INA), a low-pass filter (LPF), a variable gain amplifier (VGA), and a successive approximation register (SAR) analog-to-digital converter (ADC). The AFE IC architecture is analyzed on the system level to minimize total power consumption with high integration and optimized for an ECG sensing system. SPICE simulations of the AFE IC channel validate the ultra-low power IC design methodology for heartbeat detection with less than 1 μA/channel.