毕业设计__高精度CMOS带隙基准源的设计.doc

毕业设计
高精度CMOS带隙基准源的设计
摘要
基准电压源是模拟电路设计中广泛采用的一个关键的基本模块。所谓基准电压源就是能提供高稳定度基准量的电源,这种基准源与电源、工艺参数和温度的关系很小,但是它的温度稳定性以及抗噪性能影响着整个电路系统的精度和性能。本文的目的便是设计一种高精度的CMOS带隙基准电压源。
本文首先介绍了基准电压源的国内外发展现状及趋势。然后详细介绍了带隙基准电压源的基本结构及基本原理,并对不同的带隙基准源结构进行了比较。接着对如何提高带隙基准的电源抑制比以及带隙基准电压源的温度补偿原理进行了分析,还总结了目前提高带隙基准电压源温度特性的各种方法。在此基础上运用曲率校正、内部负反馈电路、RC滤波器、快速启动电路,设计出了具有良好的温度特性和高电源抑制比的带隙基准电压源电路。最后应用HSPICE仿真工具对本文中设计的带隙基准电压源电路进行了完整模拟仿真并分析了结果。
模拟和仿真结果表明,电路实现了良好的温度特性和高电源抑制比,0℃~100℃温度范围内,/℃,在1Hz到10MHz频率范围内平均电源抑制比(PSRR)可达到-80dB,启动时间为700。
关键词: 带隙基准电压源; 温度系数;电源抑制比;
Abstract
Voltage reference is the vital basic module which is widely adopted in analog circuits. It can supply a voltage with high stability. The power supply, technics parameter rand temperature has lesser effete to this voltage. Its temperature stability and antinoise capability influence the precision and performance of the whole system. The purpose of this article is to design a high precision CMOS bandgap voltage reference.
In this article, the present situation and developmental trend of voltage reference studies both at home and abroad are presented. The structure and principle of voltage reference are analyzed in detail, and then the different structures of bandgap voltage reference pared. By analyzing the power supply rejection ratio (PSRR) and the principle of pensation, the method of improving the temperature characteristic is summarized. The design of a bandgap voltage reference circuit with high power supply rejection ratio and good temperature characteristic pleted by applying curvature emendation, inside negative feedback technology, RC filter and fast start-up circuit. At last, the circuits have been simulated with HSPICE simulation tools.
The simulation results show that,the circuit with good temperature characteristic and high power supply rejection ratio, and at the temperature range of 0℃ to 100℃, the temperature coefficient(TC) is about
/℃. In the frequency range of 1Hz to 10MHz, the average power sup