A feed-forward compensated FVF LDO regulator with no on-chip compensation capacitors

Abstract

This paper proposes a capacitor-free Flipped Voltage Follower (FVF) Low Dropout (LDO) regulator. To stabilize the feed-back loop, the proposed multi-stage FVF LDO regulator does not require a Miller compensation capacitor or physical resistor. A capacitor-free internal structure improves closed-loop bandwidth while saving area in the LDO regulator. In this work, a large feed-forward transconductor (gmf) is proposed, which generates a strong left-half-plane (LHP) zero while consuming a small bias current. The large feed-forward transconductor boosts the LDO regulator’s DC gain and bandwidth. The proposed FVF LDO regulator is implemented in standard 130nm CMOS technology and achieves a unity gain frequency of more than 35 MHz while consuming a total quiescent current of 97μA. The proposed FVF LDO regulator has an active area of 0.0054mm2, which is less than many other LDO regulators that have been reported.