Analysis, Design and Implementation of Power-Efficient DC-DC Converters for Biomedical and IoT Applications

This thesis focus on improving the power efficiency of DC-DC converters for two different applications. In the field of implantable medical devices, electrical stimulation has been used as an established treatment for several diseases. It aims to deliver a well-defined amount of charge to the tissue in order to build up a specific electric field...

A Switched-Capacitor DC-DC Converter Powering an LC Oscillator to Achieve 85% System Peak Power Efficiency and -65 dBc Spurious Tones

In this paper, we propose a new scheme to directly power a 4.9-5.6GHz LC oscillator from a recursive switched-capacitor DC-DC converter. A finite-state machine is integrated to automatically adjust the conversion ratio and switching frequency of the converter such that its DC output voltage is within ±5% of the desired 1V across input voltage...

Analysis and Design of Power Supply Circuits for RF Oscillators

This article presents guidelines for designing the power supply blocks of RF oscillators. To preserve their spectral purity, the requirements on the noise and ripple of the supply voltage are firstly evaluated based on the oscillator supply pushing factor and the oscillator Figure-of-Merit (FOM). Those specifications are then employed to design...

An Ultra High-Frequency 8-Channel Neurostimulator Circuit with 68% Peak Power Efficiency

In order to recruit neurons in excitable tissue, constant current neural stimulators are commonly used. Recently, ultra high-frequency (UHF) stimulation has been proposed and proven to have the same efficacy as constant-current stimulation. UHF stimulation uses a fundamentally different way of activating the tissue: each stimulation phase is...

A Switched Capacitor DC-DC Buck Converter for a Wide Input Voltage Range

In this paper, a power-efficient multiphase Recursive Switched Capacitor (RSC) converter is presented. Conventionally, RSC converters are used to obtain many different output voltages from a fixed input voltage. Here, the converter provides a fixed output voltage of 1 V at 1 mA from an input voltage ranging from 1.4 V to 4.5 V. It has one...