Modeling and analysis of voltage controlled positive output synchronous buck-boost converter

Now a day´s use of portable devices increasing more. Such as cellular phones, digital cameras and high efficient power managing modules etc. are demanding for low output voltage ripple with fast transient response. The terminal voltage of the battery used in portable applications varies particularly depending on state of their charging conditions. In this paper, Li-ion battery is considered that provides 4.2V when it is fully charged and drops to 2.7V when fully discharged. However, the system requires a constant output voltage of 3.3V under varying load conditions. Thus, this work addresses the design and modeling of voltage controlled positive output synchronous buck-boost converter. Simulation model is developed using MATLAB/Simulink and results analysis has been carried out.