Single-inductor four-switch non-inverting buck-boost dc-dc converter

A single-inductor four-switch non-inverting buck-boost dc-dc converter was designed. Compared to other conventional buck-boost typologies, the presented converter reduces the number of external passive components and chip/PCB area. The chip was implemented by using the TSMC 0.35um 3.3V/5V 2P4M polycide CMOS process. The input voltage range of the presented converter covers the full output voltage range of a Li-ion battery, its output voltage is 3.3V, and its maximal load current is 300 mA. The die area of the chip is 1.38 ×1.80 mm ² , packed with a 40 S/B package.