A 4.1W/mm² Peak Power Density and 77% Peak Efficiency Fully Integrated DC-DC Converter based on Electromagnetically Coupled Class-D LC Oscillators and a Resonant LC Flying Impedance in 22nm FDSOI CMOS

• Published in: 2023 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits) pp. 1 - 2
• Main Authors: Novello, Alessandro, Atzeni, Gabriele, Keller, Tim, Jang, Taekwang
• Format: Conference Proceeding
• Language: English
• Published: JSAP 11-06-2023
• Subjects: DC-DC power converters; Density measurement; Power system measurements; Resistance; RLC circuits; Silicon-on-insulator; Very large scale integration
• ISSN: 2158-9682
• DOI: 10.23919/VLSITechnologyandCir57934.2023.10185344

This paper presents a fully integrated DC-DC converter based on electromagnetically coupled class-D LC oscillators. The proposed converter features a hybrid LC flying impedance, ZFLY, which lowers the converter output resistance ROUT by introducing a resonant charge exchange with the output capacitor Co. The improved ROUT provides a peak efficiency of 77% and a peak power density of 4.1W/mm 2 , marking a significant improvement with respect the state-of-the-art. The output voltage regulation is obtained with a duty-cycling control scheme that maintains the efficiency loss <2% from 0.003W/mm 2 up to 2.1W/mm 2 . The proposed DC-DC converter is fabricated in a 22nm FDSOI CMOS process with a total area of 0.33mm 2 .