In a method for a DC-DC power conversion performed by a switching mode buck voltage
converter, the power conversion is split into two or more stages, and a feed-forward
signal is generated by one of the stages and sent to another stage prior thereto.
The feed-forward signal is generated by responding to a load current transient,
such as output voltage drop, ON-duty increment or decrement occurred in the PWM
control loop, error amp output swinging, and any other detectable signals in response
to load current transient of the voltage converter. As a result, the performance
of the DC-DC voltage converter is improved due to the prior stage modulated early
in time, and both lower ripple current and peak current in steady state operations
and fast response to load current transient conditions could be simultaneously obtained.