Low-temperature drift band-gap reference circuit based on concave-convex curvature compensation

Abstract

The invention discloses a low-temperature drift band-gap reference circuit based on concave-convex curvature compensation. A primary reference starting module and a band-gap reference core starting module are used for starting a primary reference module and a band-gap reference core module during electrification, and exiting after the primary reference module and the band-gap reference core modulenormally work; the band-gap reference core module forms a betahelp structure with a second triode and a third triode through an NMOS tube source follower connection method or a PMOS tube common-source electrode connection method, so that a problem of overlarge error caused by introduction of a base current is avoided; the primary reference module generates a primary reference voltage with the driving capacity to supply power to the band-gap reference core module and the band-gap reference core starting module, so that the power supply rejection performance of the band-gap reference is improved, and furthermore, the primary reference voltage and the first-order compensation band-gap voltage generated by the band-gap reference core module are superposed through a resistive subdivision mode,the low-temperature drift band-gap reference of the concave-convex curvature compensation can be generated, a temperature drift coefficient is 4 ppm, and the requirements for high-precision application occasions can be well met.

Description

technical field [0001] The invention relates to electronic circuit technology, in particular to a low-temperature drift bandgap reference circuit based on concave-convex curvature compensation. Background technique [0002] As an indispensable module in DC / DC converters, AC / DC converters, linear regulators, digital-to-analog converters and other circuits, the bandgap reference circuit determines the performance of the entire analog circuit and even the chip. Bad and functional fulfillment. In the CMOS process, the current amplification factor β of the BJT is small. Under the condition of a certain collector current, the extraction of the base current will introduce a large error to the reference circuit of the traditional structure. Moreover, the temperature drift coefficient of the bandgap reference voltage after the first-order compensation is generally 30-50ppm, which seriously limits the performance of the system for high-precision systems. Contents of the invention ...

AI Technical Summary

Problems solved by technology

In the CMOS process, the current amplification factor β of the BJT is small. Under the condition of a certain collector current, the extraction of the base current will introduce a large error to the reference circuit of the traditional structure.

Moreover, the temperature drift coefficient of the bandgap reference voltage after first-order compensation is generally 30-50ppm, which seriously limits the performance of the system for high-precision systems

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