8.4‐to‐16‐bit resolution, 1‐to‐16 kHz bandwidth ADC with programmable‐gain functionality for multi‐sensor applications

Abstract

A resolution‐reconfigurable, bandwidth‐scalable analogue‐to‐digital converter (ADC) with programmable‐gain (PG) functionality for a multi‐sensor system, which encompasses various signals such as bio‐signals and battery‐level, is presented. In PG and low‐power mode, a PG first‐order noise‐shaping (NS) successive‐approximation register (SAR) ADC achieves 8.4‐to‐10.2‐bit operating up to 16 kHz while providing a gain of 1/2/4. The PG NS SAR ADC can be reconfigured as an adder and a quantiser in a delta‐sigma (ΔΣ) modulator enhancing the order of the modulator for high‐resolution. The third‐order ΔΣ modulator achieves 16.1 bits in a bandwidth of 1 kHz. The work is implemented in a 0.18 μm CMOS process with a 1.8 V power supply.

Keywords

• multisensor system
• bio‐signals
• PG NS SAR ADC
• third‐order delta‐sigma modulator
• programmable‐gain first‐order noise‐shaping SAR ADC
• PG first‐order NS successive‐approximation register analogue‐to‐digital converter