A 1500 mA load current LDO with wide power supply range in lithium-ion battery

摘要

This study proposes a maximum load of 1500 mA low-dropout regulator (LDO) for Lithium-ion battery pack dedicated to smart battery system. The proposed LDO consisting of two modules achieves a stable 2.5 V output with a power supply range from 3.9 to 20 V. Two-modules scheme provides a less power dissipation and a high stability. A pre-regulator as the first module is utilized to achieve an output voltage of 3 V and supplies for other internal circuits including the second module (core LDO). The core LDO operating at 3 V obtains an output voltage of 2.5 V with a load range from 0 to 1500 mA. To make sure the stability of LDOs, error amplifiers with miller-compensation technique are used in two modules. In addition, the core LDO utilizes a 22 μF offchip capacitor to effectively make the transient output stable. The proposed circuit has been implemented in a 0.4 μm standard CMOS process.