Numerical-control low-noise high-power-supply-rejection-ratio low-dropout regulator

The invention relates to a numerical-control low-noise high-power-supply-rejection-ratio low-dropout regulator, belonging to the technical field of integrated circuits. The regulator comprises a reference voltage generation circuit which is formed by a biasing circuit supplied with power by an external power supply, a biasing circuit supplied with power by low-dropout regulator output voltage, biasing circuit switching circuit and a numerical-control regulating circuit, an error amplifier which is formed by a first error amplifier and a second error amplifier, and a low-dropout regulator output circuit which is formed by a large PMOS tube, a frequency compensation circuit and resistance bleeder circuit and a power supply filter circuit. Through controlling the reference voltage of the LDO on a resistance control blade in a Vth multiplier, the output voltage of the LDO on the control blade can be numerically controlled. The numerical-control regulation function can ensure that the output voltage of the LDO can satisfy the design requirement in a better way under different working conditions. The LDO designed in the invention has the advantages of low noise, high power supply rejection ratio, numerical control and the like.