Fast Load Transient Response LDO with Slew Rate Enhancement Circuit

Abstract

片上系统SoC (System on a Chip)的快速发展，对低压差线性稳压器LDO (Low Dropout Linear Regu-lator)芯片的性能要求更加苛刻。更低静态功耗、更少外围器件以及更高转换效率和电源抑制比、更快响应速度已经成为LDO芯片的研究热点和发展趋势。提出了一种带有摆率增强电路的快速负载瞬态响应无片外大电容LDO，用摆率增强技术及动态偏置技术来优化LDO的摆率，在负载发生跳变时能够快速响应。 Because of the rapid development of SoC (System on a Chip), the requirements to LDO (Low Dropout Linear Regulator) chip become more and more rigorous. Lower power consumption, fewer periph-eral devices, faster response speed, higher conversion efficiency and power supply rejection ratio have become hotspot of LDO chip. In this paper, a large capacitance free LDO is proposed, which us-es slew rate enhancement technology and dynamic bias techniques to optimize slew rate of the LDO, so the transient response of the output voltage becomes fast enough when the load current changes.