Abstract：Current mode pulse-train (PT) control technique for single-inductor dual-output (SIDO) dc-dc converters operating in discontinuous-conduction mode (DCM) is proposed in this paper. To avoid cross-regulation between two outputs of SIDO buck converter, time-multiplexing scheme is used to determine which output is controlled in the time interval of time-multiplexing signal. A blank pulse is adopted to improve the performances of converter in light load, and to improve the transient performance and power conversion efficiency. A current loop is adopted to achieve cycle-by-cycle current limiting. Error amplifier and corresponding compensators as required by conventional current mode pulse width modulation (PWM) technique are not needed in PT control technique. The control technique proposed in this paper is simple and has fast dynamic response. Simulation and experimental results are presented to describe and verify the proposed technique.
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2012, Vol. 27 
