A SIDO buck converter with a load dependent controller to minimize cross-regulation

This paper proposes a single inductor dual output (SIDO) buck converter with a load dependent controller to achieve high conversion efficiency, fast transient response, and small cross-regulation, which is suitable for power management applications. The switching frequency is adjusted according to the load condition by the proposed current integrator, thus the converter can provide sufficient energy in time to load circuit and minimize cross-regulation. Meanwhile, lower switching frequency can also improve the conversion efficiency at light load condition. The proposed SIDO buck converter is implemented using TSMC 0.18 μm CMOS process. Post-layout simulations show that the cross-regulation, line/load regulations, and the load transient recovery time are less than 1.8%, 2.9%/0.83%, and 25.6 μs, respectively. The simulated peak power efficiency is 95.5%.