A 200-μW Interface for High-Resolution Eddy-Current Displacement Sensors

This article presents a low-power eddy-current sensor interface for touch applications. It is based on a bang-bang digital phase-locked loop (DPLL) that converts the displacement of a metal target into digital information. The PLL consists of a digitally controlled oscillator (DCO) built around a sensing coil and a capacitive DAC, a...

A MEMS Coriolis Mass Flow Sensing System with Combined Drive and Sense Interface

This paper describes an interface circuit for a MEMS Coriolis mass flow sensor that combines both drive and sense circuitry. The MEMS sensor consists of a suspended resonant tube, which is read-out by comb capacitors and driven into oscillation by current flowing through a drive coil in a magnet field. The interface circuit comprises a low...

Self-Aligning and Self-Calibrating Capacitive Sensor System for Displacement Measurement in Inaccessible Industrial Environments

High-precision positioning often requires high speed and high resolution displacement measurements in order to compensate for the small vibrations of critical components. The displacement sensor must be precise and stable over a long period of time to avoid expensive recalibration. This requires tight mounting tolerances, which are especially...

A High-Resolution, Resistor-Based Temperature Sensor

This thesis focuses on developing a high-resolution, energy-efficient smart temperature sensor. A resistor-based temperature-sensing structure is chosen as the core of the sensor. To digitize the core output, a low-noise readout circuit is developed. The design was fabricated in a standard CMOS technology, and the measurements were conducted to...

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

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...

An Energy-Efficient Reconfigurable Interface for Resonant Sensors Based On Ring-Down Measurement

This thesis discusses the theory, architecture design, circuit design and measurements of an ultra-low-energy reconfigurable interface circuit for resonant gas sensors. This interface circuit employs a transient measurement method. The resonant sensor is driven at a frequency close to its resonance frequency by an excitation source that is...

Energy-Efficient Capacitive-Sensor Interfaces

This thesis describes the theory, design and realization of energy-efficient capacitive-sensor interfaces that are dedicated to energy-constrained applications. The goal of this work is to explore energy-efficient capacitive-sensor interface design techniques both at the system and the circuit level.

Systematic measurement and optimization of a Universal Transducer Interface in resistive-bridge mode

The Universal Transducer Interface (UTI) is a mass-produced interface circuit which can realize the functions of measuring signals of various sensors such as capacitive sensors, resistive-bridge sensors and resistive sensors. For some of the front-ends, an instrumentation amplifier, which is implemented with dynamic-element-matching (DEM) for...

A Novel Interface for Eddy Current Displacement Sensors

In this paper, we propose a novel interface concept for eddy current displacement sensors. A measurement method and a new front-end circuit are also proposed. The front-end circuit demonstrates excellent thermal stability, high resolution, and low-power consumption. The proposed idea is analytically investigated. The demodulation principle, as...

A high-performance interface for grounded conductivity sensors

High-Accuracy CMOS Smart Temperature Sensors

Integrated smart sensor calibration