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

Abstract

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 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> in 90nm CMOS and achieves 33A/mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> current density. Digital control with a flash ADC and a digital-to-current converter improve speed-power performance by 3X.