A Linear Regulator with Fast Digital Control for Biasing Integrated DC-DC Converters

A high-voltage-tolerant 2.4 to 1.2V push-pull linear regulator with 1A output, 288ps response time, and 97.5% current efficiency for biasing integrated DC-to-DC converters is introduced. The regulator occupies 0.03mm 2 in 90nm CMOS and achieves 33A/mm 2 current density. Digital control with a flash ADC and a digital-to-current converter improve speed-power performance by 3times