A circuit and a method for controlling output current of cascaded
switching power converters having a buck type output stage are disclosed.
The circuit comprises two comparators for sensing input and output
current, a logic gate for processing the output states of the
comparators, and a pulse width modulator circuit for receiving the output
of the logic gate and for controlling a switching power converter in
accordance with this output. The method comprises simultaneous monitoring
current in the stages of the converter, comparing the currents to the
corresponding reference levels, generating the corresponding error
signals, and controlling a pulse-width modulator circuit of a switching
converter in accordance with these error signals.