Load-Independent Control of Switching DC-DC Converters with Freewheeling Current Feedback

In this paper, a load-independent converter with freewheeling current feedback, whose output is controlled by a comparator, is presented. This control method is very useful for single-inductor multiple-output (SIMO) converters. A single-inductor bipolar-output (SIBO) converter with the proposed control scheme is implemented in a 0.5 mum power BiCMOS process and uses 3.2 mm² of die area. The current sensing gain can be increased and and the circuit is less sensitive to switching noise than CPM converters are because the slope compensation used in CPM converters reduces the current sensing gain to comply with low supply voltage.