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The concept and design of a power-conditioning circuit for an autonomous low-power System-in-Package (SiP) is presented in this paper. The SiP's main power source is based on the use of micropiezoelectric generators. The electrical model of the power source, which has been obtained based on experimental measurements and implemented on Cadence Analog Artist's Spectre simulation environment, is explained. The model has been used to simulate the power source with the power-conditioning electronics over the entire design process. Finally, the simulated and experimental results of the developed integrated power circuits, which are formed by a rectifier and a low-power bandgap reference voltage source to define the threshold voltage for the closed-loop regulation process, are also shown. These circuits have been designed using a commercial 0.13-[micro]m technology from ST Microelectronics through the Multi-Projects Circuits (CMP) Techniques of Informatics and Microelectronics for Integrated Systems Architecture (TIMA) service. Index Terms--Electric power generation, energy scavenging, low-power electronics, power conditioning, vibrations.

The reversible ferroelectric-ferroelectric transition of morphotropic relaxor-ferroelectric lead zinc niobate-lead titanate and lead magnesium niobate-lead titanate single crystals as accessed by the mechanical compression is presented. Implications of the observation for sound projectors are presented.

A study of fabrication and characterization results of piezoelectric micromachined ultrasonic transducers (pMUTs) based on 2-micrometer thick Pb(Zro.53Tio.47O3) (PZT) thin films is described. A transmit-receive experiment with two quasi-identical pMUTs showed significant signal transmission up to a distance of 20cm in air and 2 cm in the test liquid.

A diaphragm-type piezoelectric micromachined ultrasonic transducer (pMUT), a composite coating technique based on chemical solution deposition and high-energy ball milled powder used to fabricate thick PZT films, and micromachining of the pMUTs using thick films is investigated. Results suggested that the fabricated pMUT has very good ultrasound-radiating performance and can be used to compose pMUT arrays for generating ultrasound beam with high directivity in numerous applications.

Usage of light diffraction tomography to measure the acoustic field of micromachined ultrasonic transducers (MUT) in cases in which standard methods like hydrophone and microphone measurements fail is demonstrated. The results reveal that the air-coupled MUTs in the frequency range of about 1MHz as well as the extreme near field of a miniaturized continuous wave 10 MHz water-loaded transducer were successfully characterized with light diffraction tomography.

Manganese modified (1-x)BiScO3-(x)PbTiO3 (BSPT) compositions near the morphotrophic phase boundary are investigated and the electrical behavior is characterized at high temperatures, and a full set of material constants is determined using the resonance method. Studies revealed that these data should provide a basis to perform future theoretical analysis as well as device design, the temperature of the properties and very high RC modifying BSPT as a new material for high temperature actuation and sensing applications.

A study is conducted to investigate the length extensional (33-mode) electromechanical properties and their stability for morphotropic (001) oriented and poled multidomain PMN-PT single crystals when driven by a large electric field under a combined DC bias field and compressive mechanical stress. It is found that the remarkable small signal length extensional coupling (K33 > 0.99) and other electromechanical properties of morphotropic PMN-PT single crystals prevail under large drive.

Theoretical simulations are performed on a new [100]-oriented IV-VI lead-salt midinfrared (IR) edge-emitting laser and compared with the conventional [100] oriented laser. The simulated results indicate that with optimized laser structure and modestly reduced Auger recombination [10] IV-VI lead-salt edge-emitting laser could produce output power of about 10 mW at room temperature.

Improvements of the d(sub 33) co-efficient for thick-film lead zirconate titanate (PZT) layers are detailed. The combination of small and large particles does increase the d(sub 33) of the film and justifies the investigation and it is shown that the consistency of the results can be increased in comparison to the ball milled devices, although they are not as consistent as the attritor3 devices.