Effects of Powering Low Voltage, High Current Loads on Components Power Design Perspective

摘要

Increasing demands on computing power and information access have placed special challenges on the power industry and their component suppliers. In a mission to provide micro-processors and ASIC's with higher MIPS count and higher clock speeds, manufacturers of these devices have continuously increased transistor counts to accommodate higher level of function and more computing power along the curve of the ever popular Moor's Law. In order to accommodate this trend, the actual size of the transistors on silicon has been steadily reducing from "common day" 0.35micron to 0.18micron for the next generation of silicon. Companies such as Intel, AMD, and Motorola have been investing heavily into building large fabs in order to prepare for high volume manufacturing.rnPower designers are challenged to take on the following facts as a result of the above trend:rn1. Load currents are steadily increasing in time.rn2. Operating voltages are decreasing as a result of smaller transistors.rn3. Slew rates from no-load for full-load and vice versa have been increasing exponentially to meet the new environmental standards and "full power on demand" requirements.rn4. Above all, the efficiency of converters has remained steady remained constant at approximately 85% In some cases efficiency is increased to accommodate reduction of ambient temperatures in "machines" which are more powerful and smaller in size.rnThe above four factors have a significant effect on the power component and their application. Their implication will be discussed in light of FET's, capacitor technology, regulation and ESR.