文件名称:Low-voltage LDO Compensation Strategy
文件大小:384KB
文件格式:PDF
更新时间:2013-12-23 18:15:56
LDO Low-voltage Compensation
In this communication, we propose a Miller compensation technique for low voltage LDO regulators which makes use of a current amplifier. The analysis shows how to design the compensation network when no voltage buffer is placed between the LDO error amplifier and power device and suggests a low supply voltage circuit topology that allows to compensate with a reasonably low integrated capacitance, to avoid oscillations due to the complex-conjugate poles at high output currents and to obtain acceptable under/overshoots during fast transient load variations. The designed LDO regulator can work with a supply voltage down to 1.2V with a drop-out voltage of 200mV at maximum load current of 100 mA; the integrated compensation capacitance is 25 pF, the load capacitor being equal to 1 μF. Simulations in good agreement with the theoretical results are also shown.