A 0.6-1 V $\mathrm{V}_{\text{IN}}$ Soft-Switching Low Dropout Regulator with 31.3 A/mm2 Current Density, 99.99% Current Efficiency, and 2.04 fs FoM
Jeongmyeong Kim, Changjoo Park, Wanyeong Jung · 2024
This paper presents a soft-switching LDO, which takes advantages of analog and digital LDOs. A soft quantizer enables smooth switching of power FETs like an analog LDO. Inverter-based buffers provide rail-to-rail output voltages to power FETs like a digital LDO and offer fast transient response using a push-pull structure even with a small dropout voltage$(\mathrm{V}_{\mathrm{D}\mathrm{O}})$of 50 mV. A test chip fabricated in a 65 nm CMOS process achieves a high current density of 31.3 A/mm2 at 1 V$\mathrm{V}_{\text{IN}}$, a current efficiency of 99.99% at 0.6 V$\mathrm{V}_{\text{IN}}$, and a fast transient response of a 102 m V voltage droop at a 90 mA/4 ns load condition with a 0.6 V$\mathrm{V}_{\text{IN}}$.