The invention discloses a high-frequency high-PSRR LDO circuit based on current sampling feedback, and belongs to the technical field of integrated circuits. The circuit comprises a first
transconductance operational amplifier, a second
transconductance operational amplifier, an I-V conversion circuit, a power tube, a
mirror image power tube, a sampling
resistor RS, a resistance feedback network and a load end. The first
transconductance operational amplifier amplifies the difference value between the standard reference
voltage and the feedback
voltage and outputs current; the second transconductance operational
amplifier detects the
voltage difference between the two ends of the sampling
resistor RS and amplifies the output current; the I-V conversion circuit converts the two currents into voltage signals to
control grid voltages of the power tube and the
mirror image power tube; the
mirror image power tube samples output current of the power tube in equal proportion, and the output current is converted into voltage through a sampling
resistor RS and fed back to the second transconductance operational
amplifier; the resistance feedback network divides the output voltage to generate a feedback voltage. A series
negative feedback structure is formed through current sampling feedback, and equivalent impedance from a power supply to output is improved, so that the high-
frequency band power supply rejection ratio is remarkably enhanced, the problems that a traditional LDO is poor in high-frequency PSRR, a circuit is complex and the area is large are solved, and
broadband high PSRR is achieved.