Low Temperature Drift High Power Supply Rejection Ratio Bandgap Reference Circuit Based on Exponential Compensation

Abstract

Low temperature drift high power supply rejection ratio bandgap reference circuit based on exponential compensation, including pre-regulation module, pre-regulation start-up module, bandgap reference core module and bandgap reference core start-up module, the bandgap reference core module is used to generate reference voltage , the fifteenth PMOS tube with common source connection forms a βhelp structure, which avoids the problem of too small a value of β in the CMOS process, which causes excessive errors in the base current; at the same time, the high-order curvature of the reference voltage is compensated by the ninth resistor R9 The structure is embedded in the βhelp structure, which significantly reduces the temperature drift coefficient of the reference output voltage; the bandgap reference core startup module is used to make the bandgap reference core module break away from the degeneracy point; the pre-regulator module is used to generate a bandgap reference core module The local voltage supplied by the bandgap reference core start-up module, through the self-adaptive drive structure, not only ensures the driving capability of the pre-regulation structure but also effectively improves the power supply rejection ratio of the reference output voltage; the pre-regulation start-up module is used to make the pre-stabilization The compression module leaves the 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] Bandgap reference circuit is an indispensable module in DC / DC converters, AC / DC converters, linear regulators, digital-to-analog converters and other circuits. Its performance determines the performance of the entire analog circuit and even the chip. Bad with function implementation. 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 mixed-signal systems, since the high-frequency coupled noise of the digital circuit module can feed through the analog circuit module through the source, ground and analog-digital interface, it will have a f...

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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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