Gate drive method extends supply's input range:
06/26/03 EDN-Design Ideas / Industrial and telecom
applications often require a nonisolated, low-voltage supply
from a high-voltage input. IC manufacturers have responded
to that need with the application of high-voltage processes
and offer control ICs that work to 50V and higher. That
voltage is sometimes insufficient, and you need further
design techniques to extend the input voltage...