Buffer circuit used for LDO

The invention belongs to the technical field of integrated circuits, and relates to a buffer circuit used for an LDO. Compared with a traditional LDO circuit, in the buffer circuit used for the LDO, the buffer circuit is added; the buffer circuit can improve the driving capacity of an error amplifier, so that the transient response of the LDO is drastically improved; besides, since the buffer circuit is composed of a source follower, the source follower has an extremely low output resistance, and therefore, a pole P3 generated by an output end of the error amplifier can be pushed to a higher frequency, so that the stability of the circuit is not influenced by the pole P3; more importantly, in the buffer circuit, through the design of the circuit structure, the quiescent current of the buffer is reduced, which has very significant importance in the reduction of the overall power consumption of the LDO circuit.