Reference voltage module and temperature compensating method thereof

Abstract

Aiming at the problem that it is difficult to realize high-order temperature compensation without increasing process cost under standard CMOS process conditions, the invention discloses a low temperature coefficient, low noise, high-precision reference voltage module and a temperature compensation method thereof. The reference voltage module includes the current IV#_[bc] generating circuit, the current IPTAT generating circuit, the self-starting circuit, the output current IV#_[bc] of the current IV#_[bc] generating circuit, and the output current IPTAT of the current IPTAT generating circuit Two outputs are respectively connected to a high-order current INL generating circuit, and the second-order current INL of the high-order current INL generating circuit is output to a fully differential reference voltage circuit through the proportional coefficient C1, 2, and the current IV#_[bc] passes through The proportional coefficient A and the current IPTAT are respectively output and connected to the fully differential reference voltage circuit through the proportional coefficient B. The temperature compensation method is to perform full-temperature section curvature correction in the high-order current INL generating circuit, and at the same time perform resistance fine-tuning in the full-differential reference voltage circuit.

Description

Technical field: [0001] The invention relates to a reference voltage module in A / D (analog-to-digital converter) and D / A (digital-to-analog converter) and a temperature compensation method thereof. Background technique: [0002] The reference voltage module is a key module of high-performance A / D and D / A converters. The traditional reference voltage is to generate a voltage close to the bandgap when the absolute temperature is zero by adding the voltage of PTAT (diode forward voltage drop and proportional to absolute temperature), that is, first-order compensation. Its temperature characteristics are poor, generally above tens of ppm / °C, and it is difficult to meet the needs of high-performance circuit systems. In the bipolar process, high-order temperature compensation is developed, and the second-order curvature correction compensation is the main one, which improves the temperature characteristics. However, the reference voltage is realized in the standard CMOS (complem...

AI Technical Summary

Problems solved by technology

[0003] The present invention aims at the improvement of temperature characteristics in the whole working temperature range brought about by segmental curvature correction and fine-tuning in a partial temperature range, which is difficult to realize high-order temperature compensation without increasing the process cost under standard CMOS process conditions. It is not large, but it also has the disadvantages of large output impedance and noise, and poor common-mode rejection ratio of the power supply. It provides a low temperature coefficient, low noise, high-precision reference voltage module and its temperature compensation method

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