A wide range voltage stabilizing circuit for LDO regulator

Abstract

Large size and thick oxide transistors are usually used in the design of Low Dropout Linear Regulator(LDO) in order to increase the upper limited voltage of input supply voltage，but this will increase the area of the circuit. In order to solve this problem, this paper proposed a wide range voltage stabilizing circuit based on an improved Wilson current mirror structure, which provides power and bias for LDO. The simulation results show that the external supply voltage range from 3.5 V to 6 V can be converted to 1.8 V supply voltage, so that the LDO core circuit can still use 0.18 μm MOS transistors under the high input supply voltage, which can reduce the chip area. And it can bring convenience to the design of LDO analog module.

Keywords

• LDO
• linear regulator
• wide range voltage stabilizing circuit