Exponential compensation-based low-temperature-drift high-power-source rejection ratio band-gap reference circuit

Abstract

The invention relates to an exponential compensation-based low-temperature-drift high-power-source rejection ratio band-gap reference circuit. The circuit comprises a pre-voltage stabilization module,a pre-voltage stabilization starting module, a band-gap reference core module and a band-gap reference core starting module; the band-gap reference core module is used for generating a reference voltage; a fifteenth PMOS transistor of a common source connection method forms a beta help structure, and therefore, the problem of excessively large error induced by base current due to a too small betavalue in a CMOS process is avoided; the high-order curvature compensation structure of the reference voltage is embedded into the beta help structure through a ninth resistor R9, so that the temperature drift coefficient of a reference output voltage is remarkably reduced; the band-gap reference core starting module is used for separating the band-gap reference core module from a degeneracy point; the pre-voltage stabilization module is used for generating local voltages for supplying power for the band-gap reference core module and the band-gap reference core starting module; by means of a self-adaptive driving structure, the driving capability of a pre-voltage stabilization structure is guaranteed, and the power supply rejection ratio of the reference output voltage is effectively improved; the pre-voltage stabilization starting module is used for separating the pre-voltage stabilization module from a degeneracy point.

Description

technical field [0001] The invention relates to electronic circuit technology, in particular to a low temperature drift high power supply rejection ratio bandgap reference circuit based on exponential 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. In a mixed-signal system, because the high-frequency coupling noise of the digital circuit module can be fed through to the analog circuit module through the source, ground and analog-digital interface, it will have a fatal ...

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Problems solved by technology

[0003] Aiming at the influence of the base current on the precision of the bandgap reference in the above-mentioned traditional reference source and the problem of low power supply rejection ratio, the present invention proposes a low-temperature drift high power supply rejection ratio bandgap reference circuit based on exponential compensation, and the pre-stabilization module adopts an automatic Adapt to the driving circuit, generate local voltage as the internal power supply voltage of the bandgap reference module, and provide a certain driving ability to achieve the effect of suppressing the power supply ripple; the core module of the bandgap reference adopts the βhelp structure, which avoids the BJT collector current to Influenced by the reference structure of the gap; the ninth resistor R9 is a resistor composed of a combination of positive temperature coefficient and negative temperature coefficient, and the base current flows through the ninth resistor R9, which introduces a high-order curvature compensation term to the bandgap reference current

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