Is Power Conversion Efficiency Running out of Steam as a Comparison Tool?

Power conversion efficiency has been the standard means of comparing the performance of the power converter as it provides a simple and direct way to evaluate a given converter's performance while evaluating the heat sinking and cooling requirements at the same time. The efficiency tool works very well when we have established standard input and output voltages that are more or less fixed in value. As the output voltage of the DC-DC converters for the PC and telecommunications markets started moving steadily towards the sub-one volt range, it became apparent that this method does not truly represent the performance in the same way we are used to. This paper explains why that is and propose an alternative methods that measures the performance "almost" independent of the output voltage that gives a much more accurate and unambiguous idea about the converter's performance so we introduce the concept of the effective loss resistance