An illumination aware single solar-cell VCO CCO based charge-pump energy harvesting system for SoC integration

ULTRA-low power systems such as smart dust sensors, biomedical implants and wireless sensor nodes are usually powered by batteries and hence their lifetime is limited. Solar energy is found to be a perennial power source, providing an effective solution to these systems. In micro-scale systems, the dedicated area to the transducer is too small and hence, the voltage and the power obtained is much less (mV and μW). Maximizing the transferred power from energy transducer to the storage cell is the major design objective

An illumination aware single solar-cell VCO CCO based charge-pump energy harvesting system for SoC integration

ULTRA-low power systems such as smart dust sensors, biomedical implants and wireless sensor nodes are usually powered by batteries and hence their lifetime is limited. Solar energy is found to be a perennial power source, providing an effective solution to these systems. In micro-scale systems, the dedicated area to the transducer is too small and hence, the voltage and the power obtained is much less (mV and μW). Maximizing the transferred power from energy transducer to the storage cell is the major design objective

An Illumination aware single solar-cell VCO CCO based Charge-pump energy harvesting system for SoC integration

A complete system for entire single solar-cell illumination range fully on-chip micro-scale energy harvesting is proposed. To maximize the extracted output power over the entire illumination range, optimal frequency operation and reconfigurable adaptive switch sizing techniques have been discussed. A fully digital illumination change detection block and a reconfigurable VCO/CCO (Voltage/Current Controlled Oscillator) scheme have been introduced. The proposed system has been designed in UMC 0.18-μm CMOS technology and the techniques used here offer an efficiency improvement up to 10% in both low, high illumination ranges compared to the conventional system and achieve a peak system efficiency of 67%. The objective of this system is to make energy harvester unit to drive wide range of ultra-low power applications by overcoming the challenges faced in conventional energy harvesting systems. Here, the proposed system is validated by driving ZigBee transceiver modelled electrically which consumes 200uW at supply voltage of 0.8V is driven in mid, high range solar illumination and acts as charger in low range solar illumination. Also, cold start-up circuit architectures based on nakagome voltage doubler, hybrid energy scavenging, four phase boot strapped charge pump regulator integrated with start-up scheme are designed and thorough performance comparision is presented. Finally, the most efficient solar, RF hybrid nakagome charge-pump based start-up system is layedout and post layout simulations are completed achieving the maximum efficiency of 39.64% in start-up mode. A Board level design of practical real time setup of self- powered energy harvesting system that can establish voice communication calls using zigbee transceivers is also completed pointing out the issues faced by all the commercially available energy harvesting chipsets and have been overcome in the proposed full system design

Advances in Bioengineering

The technological approach and the high level of innovation make bioengineering extremely dynamic and this forces researchers to continuous updating. It involves the publication of the results of the latest scientific research. This book covers a wide range of aspects and issues related to advances in bioengineering research with a particular focus on innovative technologies and applications. The book consists of 13 scientific contributions divided in four sections: Materials Science; Biosensors. Electronics and Telemetry; Light Therapy; Computing and Analysis Techniques

Massachusetts Domestic and Foreign Corporations Subject to an Excise: For the Use of Assessors (2004)

International audienc