DESIGN IDEAS Synchronous, Phase Modulated, Full
Bridge Converter Targets Isolated High
by Kurk Mathews
Power Applications
Introduction In networking and telecom equipment,
power supplies provide isolated low
voltage outputs from the 48V input
supply rail, with the added requirements of high efficiency (to reduce
heat dissipation) and low component
height. These requirements become
even more difficult to meet with increased power levels, because of the
corresponding component power dissipation and increased transformer
size. Simple power supply topologies
give way to more complex single and
two-stage approaches that focus on
transformer and semiconductor utilization.
One such approach, the phase
modulated full bridge converter, is a
popular choice for high power supplies. Unfortunately, until now, there
has not been a controller that offers
both the flexibility in timing control
and features (such as synchronous
rectifier outputs) to manage a variety …