A Pseudo-4-Phase Buck Converter with 94.1 % Efficiency, 1mV Output Ripple and Fast Transient Response

With the rapid advancements in low Earth orbit (LEO) satellites and next-generation 6G transmission protocol technologies, there is an increasing demand for advanced power management ICs that provide robust and efficient supply voltages. For instance, maintaining the output voltage ripple <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta \mathrm{V}_{OUT}$</tex> within a 2% variation while delivering load currents ranging from 0.1 A to 10A to multiprocessors, RF circuits, and sensors is critical. To address these challenges, multiphase buck converters [1]–[4] are often employed to enhance efficiency across a wide range of conditions. However, they encounter difficulties in managing total inductor current ripple at very low voltage conversion ratios (VCRs), such as when converting from 21V-33V down to 1V, which results in a large <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta \mathrm{V}_{OUT}$</tex>, an undesirable outcome for sensitive electronics. Reference [5] proposes a three-phase buck architecture that leverages the ratio of inductor <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{L}_{1\mathrm{R}}]$</tex> to eliminate main inductor current ripple <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{I}_{1}+\mathrm{I}_{2})$</tex> at extremely low VCRs (top left of Fig. 1). While effective under specific conditions, this approach only eliminates <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta \mathrm{V}_{OUT}$</tex> at a specific VCR (top right of Fig. 1). When the VCR changes, additional circuits are required to eliminate <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Delta \text{Vout}$</tex>.