Single-inductor-multiple-output DC-DC converter design

Abstract

• Conversion Ratios, Efficiency, Driving Capability, Cross-Regulation and Transient Response of SIMO converter has been discussed • Cross-Regulation is a unique problem in SIMO converter • Time-Multiplexing (TM) Control and Ordered Power Distributive Control (OPDC) are commonly used control method. • TM control has limited driving capability while OPDC control has large cross-regulation. • Several advanced control methods have been introduced to improve the performance of the SIMO converter. Summary (2) • Power handling capability extension - PCCM: Pseudo CCM operation - CCAH: Sequential control with frequency hopping - CMHC: CCM operation • Cross-regulation suppression - CCAH: Maintain constant average charge deliveries to the output during transient - Vestigial Current Control: move the errors to the last dummy stage - CMHC: Fast response to minimize the cross-regulation • Fast transient response - CCAH: PWM with inductor peak current prediction and frequency hopping - Vestigial Current Control: Comparator control method - CMHC: Hysteretic control with clock synchronization Summary (3) • Single-Inductor-Dual-Output (SIDO) converters have been used to demonstrate the ideas. It can be easily extended to the Single-Inductor-Multiple-Output (SIMO) converters • The same concept can also be extended to Single-Inductor- Multiple-Input-Multiple-Output (SIMIMO).