Microcantilever Array Pressure Measurement System for Biomedical Instrumentation

An analog signal processing integrated circuit for microcantilever array has been designed for pressure measurement in biomedical applications. The chip consists of analog multiplexer, instrumentation amplifier, sample-and-hold circuit, on-chip voltage and current references, successive approximation register analog-to-digital converter (ADC) and digital control unit. Root sum square (RSS) error from the overall pressure measurement system including microcantilever array and the application specific integrated circuit (ASIC) is only ±1.79 KPa within the measurement range of 0-300 KPa. The 8-bit ADC attains 45.4 dB signal-to-noise-and-distortion ratio (SNDR) and 56.4 dB spurious-free dynamic range (SFDR), while operating at 772 KHz. The integrated circuit has been fabricated using 0.35-¿m 2-poly 4-metal CMOS process technology. The chip occupies an area of 1.54 mm
²
and consumes 17.8 mW of power with a single 3.3 V supply.