带过温保护功能的高精度带隙基准电压电路设计

发布时间：2018-05-10 23:31

本文选题：带隙基准 + 曲率补偿　；参考：《西南交通大学》2017年硕士论文

【摘要】：带隙基准电压源是电源管理芯片系统中是不可缺少的一部分,在模数转换器、数模转换器、片上系统和线性稳压器等中得到大量应用。近些年来,随着数字集成电路的迅速发展,在功能上可以代替一些模拟电路模块,然而连续信号和模拟信号必须通过模拟集成电路来实现。由于温度的变化、电源噪声和负载波动等外界因素的变化,不会影响基准电压的准确性,可以为系统提供高性能高质量的参考电压,其精度对系统的性能有直接的影响,因此对基准电压源性能的优化改进显得尤其重要,高精度、低功耗和低温漂的基准电压成为当前研究的主要方向。现代电子设备芯片中通常包含有过温保护模块,为了限制芯片的温度和功耗。由于电路长时间工作在重载情况下,会导致芯片的电流增加,直接导致环境温度的变化。如果芯片的散热性不佳,热量会不断积累,使芯片的温度急剧上升,最终将芯片内部的电路烧毁,为了保护芯片必须要限制芯片的温度。本文首先介绍了带隙基准电压的背景和研究意义,以及未来发展方向,然后在理论上对带隙基准电压源的基本原理进行了分析,并对常见的几种基准结构进行分析和对比,包括Kuijk、Widlar、Brokaw和Banba等带隙基准,并且针对传统的带隙基准电压的温度系数高等缺点,设计了一种分段曲率补偿的结构,分别在低温和高温阶段对基准电压的温度曲率进行补偿,降低基准电压的温度系数,达到设计的要求,同时也考虑到整体电路功耗,以较少的电流消耗为代价大幅提高了其精度,整体提升电路的性能,然后介绍了过温保护电路的基本原理,针对传统过温保护电路稳定性差的缺点,本文采用温度系数不同的电流进行比较,产生过温保护信号,提升过温保护电路的稳定性。本文基于0.18μmBCD工艺,采用Hspice软件仿真,结果表明,电源电压在2.5V至5V的之间变化可以产生1.237V的带隙基准电压,线性调整率为0.0357%,电源电压为 5V 时,电源抑制比(Power Supply Rejection Ratio,PSRR)为 68.8dB,静态电流功耗低至4.41μA,温度在-40°C至150°C的范围内,基准电压的温度系数为2.84ppm。过温保护电路在电源电压为5V时,温度的上升和下降门限分别为150°C和135.8°C,并且电源电压在2.5V至5V的范围内温度的迟滞量变化为1.61°C。仿真结果表明,基准电压的温度系数经过曲率补偿后大大降低,并且电路具有较低的工作电流,表现出优良的性能,满足了基准源的低功耗和低温漂的设计要求;过温保护电路在电源电压波动时,其温度阈值和迟滞量具有较强的的稳定性。
[Abstract]:Bandgap voltage reference is an indispensable part of power management chip system. It is widely used in analog-to-digital converter, digital-to-analog converter, on-chip system and linear voltage regulator. In recent years, with the rapid development of digital integrated circuit, some analog circuit modules can be replaced in function. However, continuous signal and analog signal must be realized by analog integrated circuit. Because of the change of temperature and external factors such as power noise and load fluctuation, the accuracy of reference voltage will not be affected, and the reference voltage of high performance and high quality can be provided for the system. The accuracy of the reference voltage has a direct effect on the performance of the system. Therefore, it is very important to optimize the performance of the reference voltage source. The reference voltage with high precision, low power consumption and low temperature drift becomes the main research direction. In order to limit the temperature and power consumption of modern electronic devices, it usually contains an over-temperature protection module. Because the circuit works in heavy load for a long time, it will lead to the increase of the current of the chip and the change of the ambient temperature. If the heat dissipation of the chip is not good, the heat will accumulate continuously, which will cause the temperature of the chip to rise sharply, and finally burn the circuit inside the chip. In order to protect the chip, the temperature of the chip must be limited. This paper first introduces the background and significance of bandgap reference voltage, and the future development direction, then theoretically analyzes the basic principle of band-gap voltage reference source, and analyzes and compares several common reference structures. This paper includes bandgap reference such as Kuijk Banba and Banba, and designs a piecewise curvature compensation structure to compensate the temperature curvature of the reference voltage at low temperature and high temperature, aiming at the high temperature coefficient of the traditional bandgap reference voltage, and then designs a piecewise curvature compensation structure, which compensates the temperature curvature of the reference voltage at low temperature and high temperature, respectively. Reducing the temperature coefficient of the reference voltage to meet the design requirements, but also taking into account the overall circuit power consumption, at the cost of less current consumption, greatly improve its accuracy, the overall performance of the circuit, Then the basic principle of over-temperature protection circuit is introduced. In view of the disadvantage of the traditional over-temperature protection circuit, the current with different temperature coefficient is compared to produce the over-temperature protection signal and enhance the stability of the over-temperature protection circuit. Based on 0.18 渭 mBCD process and Hspice software simulation, the results show that the band gap reference voltage of 1.237 V can be generated when the power supply voltage varies from 2.5 V to 5 V, the linear adjustment rate is 0.0357 V, and the power supply voltage is 5 V. The power rejection ratio (PSRR) is 68.8 dB, the static current power consumption is as low as 4.41 渭 A, the temperature is in the range of -40 掳C to 150 掳C, and the temperature coefficient of the reference voltage is 2.84 ppm. When the power supply voltage is 5 V, the threshold of temperature rise and fall are 150 掳C and 135.8 掳C, respectively, and the hysteresis of temperature in the range of 2.5 V to 5 V is 1.61 掳C. The simulation results show that the temperature coefficient of the reference voltage is greatly reduced after curvature compensation, and the circuit has low working current and excellent performance, which meets the design requirements of low power consumption and low temperature drift of the reference source. When the supply voltage fluctuates, the temperature threshold and hysteresis of over-temperature protection circuit have strong stability.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN432

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