The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Thermo visual images are produced from thermo vision or infrared cameras and are the source of visual information in the night or darkness for observation of objects and people in widespread security systems. There is usually the need of transmission of thermal images in these surveillance thermo vision security systems. The communication systems used for this purpose introduce the noises and distortions...
In this paper we describe the most commonly used methods for analysis the mechanical properties of 3 types LTCC substrates (DuPont 951, DuPont 9K7, MuRata) based on three- and four-point bending as well as Dynamic Mechanical Analysis (DMA). The results of analysis show that the four-point bend test indicates a distribution of stress in the substrate with more accuracy and points to the tendency of...
This paper focuses on the cooling rate of soldering process. Our target was to create a well-controlled equipment that is used to set the adjustable slope of the cooling curve with three special sections. The three sections are: near the melting point, above and below the melting point. The unit uses cooling fans to create a forced convection air flow. K-type thermocouple is used for the temperature...
During the development of an electronic module using a complex programmable logic device (CPLD) and a micro-controller, we noticed an abnormal behavior of the CPLD manifested as an unexpected reset of a counter. We identified a synchronous perturbation and an asynchronous perturbation as being responsible for the disturbance, both of them being related to the change in the state of a large number...
Knowledge of the materials' properties of reflection of electromagnetic waves (EMW) is necessary for understanding and modeling propagation, especially inside buildings and in urban areas. This paper presents the results of experimental determinations of these properties for several materials (Aluminium, Melamine Faced Fiberboard, and Gypsum Drywall slabs) in a semi-anechoic chamber, at several frequencies,...
A versatile optical sensor which utilizes localized surface plasmon resonance (LSPR) on gold nanoparticles (Au NPs) was developed and investigated. Gold nanoparticles in various size and distribution were generated by thermally annealing gold thin films (15–30 nm) which were sputtered on glass substrate. A measurement setup consisting of a microfluidic cell and an optical spectrophotometer was constructed...
Characterization method for active layers for microelectrodes of electrochemical and gas sensors using scanning electron microscopy (SEM) is presented. In order to achieve maximum sensitivity and selectivity of the sensor, it is necessary to obtain precise knowledge of electrode's surface. Characterization was made using FEI Magellan SEM equipped with TLD secondary electron (SE) and CBS back-scattered...
In the paper technology and properties of a differential pressure sensor utilizing ultrasonic waves are presented. The device consists of a LTCC (Low Temperature Co-fired Ceramics) membrane with PZT (Lead Zirconate Titanate) active layer with two interdigitated transducers (IDTs). The sensor is a completely ceramic structure equipped with two gas inlets, hence measurements of differential pressure...
The paper investigates and compares two different solutions to improve a printed circuit board designed for a portable computer main board. The issue represents the analog circuits and switching power supplies. The main example is a simple analog circuit, low dropout regulator (LDO), integrated into a complex analog circuit. The LDO stability versus the printed circuit board (PCB) design rules represents...
Thermal Interface Materials are used in microelectronic packaging for reducing so called thermal resistance between heat source and heat sink. They are commonly used, often in form of thermally conductive adhesives, as an attaching materials for fixing silicon chips in the integrated circuits. Therefore, beside the thermal properties, a good mechanical strength of TIMs is required. Within this paper...
This paper deals with the influence of the dried no-clean SAC305 solder paste on the spreading factor. Drying was defined by time between stencil printing and reflow soldering. Main investigated parameter was spreading, which is percentage difference between diameter of circle of solder paste after printing and diameter of circle after soldering.
During the surface mount technological process the assembled PCB is exposed to heat when molten solder alloy wets the surfaces and creates future solder joints. The PCB with all components should ideally be exposed to the same temperature profile during the soldering process. The temperatures differ throughout the PCB due to different thermal capacities of used materials and components even though...
The paper presents a pilot hands-on project in which 73 Bachelor students have taken part. This project addresses a key issue in the education of future electronic engineers: lack of practical activities. For the time being, this activity is placed in the middle of the academic training undergone by Bachelor students. In general, the disciplines which are found in the curricula have the following...
A microelectronic circuit of block-elements functionally analogous to two hydrogen bonding networks is investigated in the present paper. The hydrogen bonding networks are extracted from Michaelis complex of β-lactamase protein. They are described by electrical circuits. The hydrogen bonds of the networks are presented by three- or four-terminal block-elements in the juxtaposed electrical circuits...
This paper presents a new CMOS differential input FM quadrature demodulator for integrated circuits. The proposed circuit is based on Bilotti's quadrature demodulator that uses an external differential phase shift network and a differential phase detector with a single ended output. The phase detector is represented by an analog multiplier implemented with a Gilbert cell and the phase shift network...
This paper deals with the application of SPC methodology to service processes. SPC methodology is an important tool in industry because it helps find variability in processes. Any variability is undesirable because it causes deviation from the target value. Service processes are different in the specific ways and SPC methodology is suitable tool for measuring, controlling and eliminating of variation...
Potential applications of different thermography techniques for the fault diagnostic in packaged integrated circuits (ICs) in order to detect, evaluate, and localize latent and hidden defects are discussed. We present the four basic thermography techniques for qualitative and quantitative non-destructive diagnostic of sub-surface defects — passive, pulsed, step-heating, and lock-in. The results and...
Integrated cavities, screen-printed passive components and channels are common parts of 3D micro-fluidic devices fabricated in low temperature co-fired ceramics (LTCC) technology. However, realization of defect-free structures without cracks, sagging of cavities or channels is challenging and strongly influenced by quality of lamination and firing processing conditions. Lamination technique based...
Consumer electronics such as portable devices (laptops, smartphones) become smaller, thinner and more powerful. In such devices a passive cooling begins to play a dominant role in heat dissipation process. In passive cooling systems thermal resistance of thermal path between semiconductor junction and radiator should be progressively reduced. It can be done by application of efficient (high thermal...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.