摘要
分析了LDO稳压器的稳定性问题,在此基础上提出了一种新型的动态补偿电路,利用M O S管的开关电阻、寄生电容等构成的电阻电容网络,通过采样负载电流而改变M O S开关管的工作点或工作状态,即改变开关电阻、寄生电容的值,从而实现动态的频率补偿,保证了LDO稳压器的UGF(U n ity F requency)基本不随负载变化,使其在所有负载内均能稳定工作。与传统方法相比,该电路具有恒定的带宽,大大提高了系统的瞬态响应性能,使LDO稳压器具有较高的电压调整率和负载调整率。
This paper analyses the stability problem of LDO, then gives a novel mobile compensation circuit. By using resistance and capacitance of MOS consist the resistance-capacitance network ,this circuit compensate frequency by transfer the work point with sampling current and resistence-capacitance value of MOS,leading to the work stability for all loads of LDO. Comparing with conventional methods,it keeps the bandwidth stable to improve the performance of transient response greatly,and makes the LDO have higher line regulation and load regulation specification.
出处
《现代电子技术》
2005年第22期88-90,共3页
Modern Electronics Technique
