The TPA3113D2 is a 6-W (per channel) efficient, Class-D audio power amplifier for driving bridged-tied stereo speakers. Advanced EMI Suppression Technology enables the use of inexpensive ferrite bead filters at the outputs while meeting EMC requirements. SpeakerGuard™ speaker protection circuitry includes an adjustable power limiter and a DC detection circuit. The adjustable power limiter allows the user to set a ''virtual'' voltage rail lower than the chip supply to limit the amount of current through the speaker. The DC detect circuit measures the frequency and amplitude of the PWM signal and shuts off the output stage if the input capacitors are damaged or shorts exist on the inputs.
In all possible industrial, military and household/personal applications, the number of digital devices operating with data rates of hundreds of Megabits, using processor chips with Gigahertz clocks, has increased astronomically. At the same time, a myriad of popular RF receivers like portable telephones, laptop PCs with integrated wireless modems, wireless Internet, and other electronic devices, are becoming ubiquitous, such that the number of sensitive, licit receivers operating within a square kilometer of an urban area can be counted in tens of thousands. In the crowded space that they share, the conjunction of both events is increasing the number of potential interference situations, especially in the upper VHF and UHF regions where spurious radiations are most difficult to contain. There is, in addition, a growing, although controversial, concern about the possible health hazard caused by long exposure to near fields of low power radio transmitters. All these aspects result in a continuous effort for lowering RF radiations.This new edition of Controlling Radiated Emissions by Design retains the step-by-step approach for incorporating EMC into every new design, from the ground up. Quite different from other classical EMC books, it approaches the problem from a development engineer's viewpoint, starting with the selection of quieter IC technologies, their implementation into a noise-free printed circuit layout, and the gathering of all these into a low radiation packaging, including I/O filtering, connectors and cables considerations. Equally far from a cookbook of recipes, all guidelines are supported by thorough, but relatively easy and comprehensive calculated examples, allowing a quantitative design, instead of purely qualitative. New to this edition is material on surface mount techniques, IC's ground-bounce, random-versus-periodic frequency spectra and recent progress in low cost ferrite and filter components. Also included is detailed information on radiation from high-speed chips (e.g. Pentium 200 MHz) and the efforts by some manufacturers to reduce it. The book has numerous tables, all of which have been updated to reflect the latest changes in the field, including a brief overview of the U.S. and worldwide emission tests.Controlling Radiated Emissions by Design is an invaluable tool for helping design engineers, EMC specialists and technicians develop more efficient and economical control of emissions.
Near-field scanning, performed in close proximity to the tested object, is gathering increasing interest as an effective technique for estimation of radiating fields, spatial and frequency localizations of radiating sources, electromagnetic compatibility (EMC) compliant verification of complex electronic devices, and development and verification of circuit models for a dedicated model-based development process.Miniature field sensors, exhibiting high spatial resolution, are of interest due to fine geometries of conducting networks used in modern integrated circuits (ICs). Unfortunately, decreasing the sensor size leads to reduced sensitivity and thus, measurement of electromagnetic field distributions with high spatial resolution becomes a challenging task. One approach to obtain highly resolved field data with increased sensitivity is the use of integrated active sensor including not only the sensing part of the probe but also active circuitry such as preamplifier.This dissertation presents the design, implementation, and characterization of miniature passive sensors, differential amplifiers, and integrated active near-field sensors in GaAs pHEMT technology. The circuit topologies for the amplifiers and the sensor integration techniques are described and the performance of the amplifiers is demonstrated in the frequency range from 100 MHz to 10 GHz. The operability of the designed sensors is demonstrated with the proposed measurement techniques. Switchable double-input integrated active sensors and mixed-mode amplifiers with both differential- and common-mode gain are implemented and characterized.An integrated active loop sensor is also designed in SiGe HBT technology and characterized. The comparable performance of the active loop sensor in this technology opens the prospect to integrated active sensors with post processing circuits on chip.
A fast and rigorous hybrid time-domain simulator for analyzing wave interactions with complex structures involving electrically large platforms along with cable-interconnected antennas, shielding enclosures, and printed circuit boards is described. To efficiently simulate such complex structures, three different solvers are hybridized: A TDIE-based field solver for computing external fields on platforms, antennas, enclosures, boards, and cable shields, a MNA-based circuit solver for computing currents and voltages on circuits, and a TDIE-based cable solver for computing guided fields along cables. Field, circuit, and cable solvers are interfaced at cable terminations and along the cable shields, which results in a coupled system of equations that is solved simultaneously at each time step. Computation of the external and guided fields is accelerated using FFT-based algorithms and parallelization. The resulting solver permits the analysis of electrically large and geometrically intricate structures loaded with cables. The accuracy, efficiency, and versatility of the hybrid simulator are demonstrated by analyzing several EMC/EMI problems.
This volume contains some researches regarding to the Electromagnetic Compatibility domain (EMC), with applications in navigation, including problems concerning the simulation of disturbing electromagnetic interferences between electric and electronic equipment. Furthermore, the effects of the electromagnetic field on human body are analyzed. The main themes approached are: calculation of the feedback electromagnetic field, electromagnetic interference in case of onboard naval ships computers', simulation of the electromagnetic disturbances against an electronic circuit, a simulation model of the electric discharges and their effects on the human body, a simulation model to produce a high energy electromagnetic pulse by a Flux Compression Generator (FCG), a physical electric model of the human body exposed to the action of the electromagnetic environment and, finally, some issues regarding the EMC shielding.