All CMOS Low Drop-Out Regulator with Large Supply Currents for System using Li-ion Battery

In this paper, low drop-out (LDO) regulator for system using lithium-ion (Li-ion) battery is proposed. The new LDO consists of a current supply circuit (CSC) and a bias voltage generator (BVG). The new LDO can stability converts the battery voltage V
_DD
from +3.3 V to +4.5 V into the reference voltage V
_REF
of +3.0 V. The fluctuation rate DeltaV
₀
is less than about 1% and the power conversion efficiency eta is around 91% under the conditions of the load operating frequency f of 20 MHz, the draw currents I
₀
of 200 mA and the battery voltage V
_DD
of +3.3 V. Furthermore, the proposal circuits execute very high-efficiency conversion and it is very suitable as LDO regulator for system using Li-ion battery