Pseudo sliding mode control for a positive Buck-Boost converter IC in 0.13 µm CMOS

A nonlinear controller, based on the sliding mode theory, has been designed and integrated, together with the power stage and gate drivers, in a modern 0.13 µm CMOS technology. The targeted application is a positive Buck-Boost converter for portable battery-powered devices. The controller structure, combined with an innovative mode selection algorithm and a fixed operating frequency, is capable of excellent dynamic performance, which has been verified and confirmed by experimental results. In this paper, a novel implementation of the sliding function generation is shown. The silicon area footprint of the controller is 0.018mm², confirming that the proposed implementation strategy leads to a compact and efficient realization.