Design of an Energy-Efficient Interface Circuit for a MEMS-based Capacitive Pressure Sensor

Design of an Energy-Efficient Interface Circuit for a MEMS-based Capacitive Pressure Sensor

Rajendran, L.

Pertijs, M. (mentor)

Electrical Engineering, Mathematics and Computer Science

Microelectronics & Computer Engineering

2013-09-27

This thesis presents an incremental ?? capacitance-to-digital converter (CDC) that serves as an interface circuit for a MEMS-based pressure sensor. The thesis presents a systematic analysis of the CDC and compares different CDC architectures. A novel non-linear CDC is also proposed and analysed. Energy-efficiency of the CDC is improved by implementation of various design techniques like double sampling, system-level chopping and a novel inverter-based OTA. The CDC has been designed in such a way that it can operate with either an on-chip or external pressure sensor. The CDC can be tuned to compensate for a wide range of baseline capacitance. The CDC operates over a pressure range of 0-1.3 bar and achieves a pressure resolution of 1e?5 bar (equivalent to a resolution of 16 bits). The CDC is implemented in NXP 0.16?m 1P6M technology. The circuit design and layout of the CDC are presented. The CDC consumes 2.33?A from a 1.2V supply resulting in an energy consumption of only 2.01nJ, a significant improvement over the state-of-the-art.

pressure-sensor interface
energy-efficiency
double sampling
inverter-based OTA
incremental ?? ADC

http://resolver.tudelft.nl/uuid:b6b6915b-ac95-45ad-838d-c8fad5b8a171

2014-12-30

Student theses

master thesis

(c) 2013 Rajendran, L.