The topology selection, design, and performance evaluation of an on-board d
c/dc converter, which delivers power from a 48-V input to a 1.2-1.65 V/70 A
microprocessor load, are presented. It was shown that the symmetrical half
-bridge topology with the current doubler and synchronous rectifiers is a s
uitable approach for this application. The measured full-load efficiency of
a 200-kHz experimental half-bridge converter was higher than 82% in the en
tire output and input voltage range.