J. Jakovenko

Thermal simulation and validation of 8W LED Lamp

This work deals with thermal simulation and characterization of solid state lightening (SSL) LED Lamp in order to get precise 3D thermal models for further lamp thermal optimization. Simulations are performed with ANSYS-CFX and CoventorWare software tools. The simulated thermal distribution has been validated with thermal measurement on a commercial 8W LED lamp. Materials parametric study has been carried out to discover problematic parts for heat transfer from power LEDs to ambient. The objectives are to predict the thermal management by simulation of LED lamp and environment and to get more insight in the effect of lamp shape and materials used in order to design more effective LED lamps.

GaAs Thermally Based MEMS Devices—Fabrication Techniques, Characterization and Modeling

Silicon (Si) based MicroElectroMechanical Systems (MEMS) are now well understood and widely used in various integrated micromachined microsensors and microactuators. In relation to this, gallium arsenide (GaAs) offers a number of material-related properties and technological advantages over Si [1]–[3]. These include well know properties, such as direct band gap transition and high electron mobility.

Temperature dependence of the pyroelectric behaviour in GaN/AlGaN

So far the dependence of the spontaneous polarization coefficient for GaN and AlN on temperature has been measured to be minimal, which corresponds with expectation that the spontaneous polarization is reduced at the elevated temperatures of interest. There are also no reports on the piezoelectric polarization at higher temperature. This paper is initial study on the influence of temperature related pyroelectric behaviour in GaN/AlGaN. Summarize recent findings and consideration.

Incremental Control Techniques for Layout Modification of Integrated Circuits

A R T I C L E I N F O A B S T R A C T Article history: Received: 28 April, 2017 Accepted: 11 June, 2017 Online: 20 July, 2017 Analog layout is created in integrated circuits (IC) computer aided design (CAD) environment and during realization requires a lot of modifications of database objects. Because database objects modification is time consuming, then any improvement and simplification of modification flow in IC CAD environment can increase layout productivity. A proposed new modification concept can speed-up layout work and is very intuitive and easily put into practice. In advance, it allows to apply modern gesture tracking devices for control. By simplifying control of layout object modifications, the productivity of analog layout creation has been improved in the range of 23% to 66%.

Direction Sensitivity Matrix with PLL Temperature Sensor

In the paper there is presented temperature transducer with PLL signal processing of sensor data. The principle of temperature sensor is based on the MOS structure behaviour in the temperature range. The strong and weak inversion modes are used. There is used matrix of temperature sensors in the design of air flow sensor. Various arrangements of temperature structure are designed. The new circuits design is used

Microsystem models in integrated pressure sensor design

The paper describes design of a simple microsystem structure of capacity pressure circuit with integrated inductance on a single Si chip. Model system with corresponding software support is utilized for design. Different models were designed for simulation of the properties of the designed structure. Model of the substitute electronic circuit involves active and parasitic elements. The properties of this equivalent model are explored using the SPICE circuit simulator. Mechanical properties of the structure are explored using the CoventorWare program. Distribution of mechanical stress and boundary parameters are the most important ones. The paper describes flow of design software. Tools used for the design of integrated structure are described as well. Parasitic elements influencing resulting parameters are discussed; equivalent circuit connection of the integrated structure including calculation of theoretical numeric values of these elements is designed. Various modifications of integrated structure are designed and realized. The paper is completed with reached results.

Intelligent sensor structure for tilt measure

There is described approach to the development of functional and system model of the structure. In the paper, there is described a concept of structure of an intelligent sensor system for tilt measurement. Principle of an accelerometer is used for the measurement. The paper describes conceptual approach to the design of a tilt structure determined for integration on a chip. An accelerometer for measurement of inclination in x and y axes is used as a sensor. For construction non-standard connection with accelerometer is used. Measurement is controlled by a microprocessor. measured data are sent to a PC via RS232. The PC is used for data storage, further calculations and display of measured tilt. A hardware model has been developed for verification of properties. Model properties have been simulated using simulators of electronic circuits. The sensor system is temperature compensated. Lab View development tool is utilized for service program.