Bandgap reference psrr enhancement circuit

Abstract

The utility model discloses a band gap reference PSRR enhancement circuit relates to integrated circuit technical field, solves the problem of the power supply rejection ratio reduction caused by the inconsistent response of each bias node to power supply noise in the existing band gap reference circuit. The utility model discloses a starting circuit, PSRR enhancement circuit, BGR core circuit and compensation circuit that connect gradually, BGR core circuit includes operational amplifier circuit and main circuit, and operational amplifier circuit includes MOS tube M8, and main circuit includes MOS tube M12, and PSRR enhancement circuit includes MOS tube M9, M10, M11 and resistance R5. M11 grid connects operational amplifier output end, and drain connects R5 first end, and source connects ground, and M10 drain connects R5 second end, and grid connects R5 first end, and source connects M9's drain, and M9 grid connects M8 grid, M12 grid and R5 second end respectively. The utility model discloses through PSRR enhancement circuit and operational amplifier constitute internal negative feedback, make the response of circuit key node to power supply noise consistent, and the power supply rejection ratio of band gap reference has been improved significantly.

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