A Charge-Pump-Based SIMO Buck-Boost DC-DC Converter with Three Operation Modes

This paper presents a Charge-Pump-based SIMO (CPSIMO) buck-boost converter with three operation modes. By modifying the power stage topology of conventional SIMO buck-boost converters, the proposed converter exhibits faster transient response and higher efficiency. Moreover, an average- voltage-based mode selector is introduced to implement the smooth transition between three modes. The proposed converter is designed in TSMC 0.18 μm BCD process with a supply voltage of 2.7V-4.2V and has three outputs of 1.8V, 3.3V and 5V. Simulation results show that the proposed converter achieves a peak efficiency of 94.61% under output power of 2.8W and a load transient response time of 9μs with a 1.5W power step.