A stability design of the large current LDO based on the constant β PNP structure

Based on the analysis of the traditional LDO compensation methods, this paper introduces a stability structure based on constant β PNP structure. It is suitable for high current and bipolar LDO.This structure effectively overcomes the drawbacks of relying on increasing the output capacitance while sacrificing transient performance and the harsh demand for output capacitance of ESR compensation method.The LDO adopting the structure is verified by 3 μm 18V bipolar process, and the effect is remarkable.