On the design of single-inductor multiple-output DC-DC buck converters

Design techniques for single inductor multiple output (SIMO) DC-DC buck converters are presented. The suitable control of a multiple feedback loop enables the sharing of a single inductor with many outputs with a good stability and limited cross regulation. The method has been verified with simulations at the behavioural and transistor level to obtain four independent regulated output voltages ranging from 0 V to 1 V below the power supply voltage. The use of a suitable analog processing of errors allows obtaining a power efficiency as high as 86%.