A 233MHz, 80-87% efficient, integrated, 4-phase DC-DC converter in 90nm CMOS

We demonstrate an integrated buck DC-DC converter implemented in a 90nm CMOS technology for multi-Vcc microprocessors. High switching frequency (100-317MHz), 4-phase topology, and fast hysteretic control reduce inductor and capacitor sizes by 1000x, thereby enabling off-chip inductors with no magnetic core and an on-chip decoupling capacitor. The converter achieves 80-87.7% efficiency and 10% peak-to-peak output noise.