Voltage reference circuit with high power supply rejection ratio

Abstract

A voltage reference circuit with a high power supply rejection ratio comprises a starting module, a zero temperature drift current generation module and an active attenuator module; the starting module reduces a first node potential in the zero temperature drift current generation module when a power supply voltage is established, so that the voltage reference circuit is separated from a zero state, quits working after starting is completed, and the current consumption is reduced to be extremely low; the zero temperature drift current generation module clamps the loop current at a zero temperature drift point through an operational amplifier so as to generate zero temperature drift current, and outputs the zero temperature drift current to the active attenuator module through a current mirror. According to the invention, the introduced current source structure composed of the active attenuator, the second PMOS transistor and the third PMOS transistor and the operational amplifier closed-loop circuit both improve the power supply rejection ratio of the voltage reference circuit, and the active attenuator module converts zero temperature drift current into zero temperature drift voltage through the reference NMOS transistor in diode connection. Meanwhile, a reference voltage is output through a resistance voltage division network formed by a second resistor and a third resistor,and the power supply rejection ratio is further increased.

Description

technical field [0001] The invention belongs to the technical field of integrated circuits, and in particular relates to a high power supply rejection ratio (PowerSupply Rejection Ratio, PSRR) voltage reference circuit. Background technique [0002] The voltage reference circuit is an integral part of all electronic systems. In some special environments, not only the reference voltage generated by the voltage reference circuit is required not to change with the change of the power supply voltage and temperature, but also the reference voltage is required to be sensitive to the fluctuation of the power supply. Inhibition. The traditional bandgap reference structure is the most widely used, but its ability to suppress power supply fluctuations is low under a simple structure. Contents of the invention [0003] Aiming at the shortcomings of the above-mentioned traditional bandgap reference structure, which has a low ability to suppress power supply fluctuations, the present ...

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Problems solved by technology

[0003] Aiming at the shortcomings of the above-mentioned traditional bandgap reference structure, which has a low ability to suppress power supply fluctuations, the present invention proposes a voltage reference circuit with a high power supply rejection ratio, which solves the problem that the existing bandgap reference circuit has insufficient ability to suppress power supply fluctuations. question

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