【摘要】 通过对传统LDO频率补偿电路的极点、零点进行分析,提出一种新型动态补偿技术,显著改善了电路的性能指标。采用0.6μm BiCMOS工艺模型进行仿真,结果表明,当负载电流由1mA变化至300mA时,非主极点能跟随负载电流的增加向高频移动,系统环路单位增益带宽在195~555kHz之间,相位裕度保持在50°以上,保证了LDO在全负载范围内均能稳定工作。更多还原

【Abstract】 By analyzing the pole-zero behavior of a traditional frequency compensation circuit for LDO,a novel technique was presented and the performance was improved dramatically.The circuit was simulated based on 0.6μm BiCMOS process,the results showed that the secondary pole could follow the increasing of the load current to move to higher frequency with the load current varying from 1mA to 300 mA.The unity-gain bandwidth of the loop was 195~555kHz,the phase margin was over 50°,and the LDO could operate stably at all loads.更多还原