A startup circuit for providing a startup voltage from a high voltage DC
bus voltage to an application circuit, the startup circuit comprising an
integrated circuit package for at least a control circuit for driving at
least one power switch of the application circuit having a low voltage
terminal; a dropping resistor in the integrated circuit package having a
first terminal for coupling to the high voltage DC bus and a second
terminal, the dropping resistor dropping the high voltage DC bus voltage
to a reduced voltage and providing the reduced voltage at the second
terminal; further comprising a low voltage regulator coupled to the
second terminal for using the reduced voltage for enabling generation of
a regulated startup low voltage DC output at a preset level at the low
voltage terminal for powering at least one part of the application
circuit during startup of the application circuit, wherein the high
voltage DC bus voltage is the only voltage source provided externally to
the integrated circuit package.