Minimum Deviation Low-Frequency Ripple Shaping Controller for the Non-Inverting Buck-Boost Converter with Smooth Mode Transitions

A hardware-efficient, 3-mode controller obtaining minimum deviation response for non-inverting buck-boost is introduced. It improves on the already existing ripple shaping algorithm [1] and provides fast transient response of the output voltage. The operation of the controller is verified with a VIN ∈ [3.3,9] V, 100 W, 62.5-250 kHz experimental prototype, producing up to 5 V. Practically the smallest possible voltage deviation of the output voltage is achieved with smooth transitions between the buck, boost and ripple shaping modes.