文档介绍：华中科技大学
硕士学位论文
12位逐次逼近型A/D转换器的设计
姓名:张诗娟
申请学位级别:硕士
专业:微电子学与固体电子学
指导教师:刘三清
20050429
摘要
在现代先进的电子系统的前端和后端都将应用到 A/D 转换器以改善数字处理技
术的性能在各种 A/D 转换器中逐次逼近型 A/D 转换器是采样率低于 5 Msps 每
秒百万次采样的中等至高等分辨率应用的常见结构由于逐次逼近型 A/D 转换器具
有低功耗小尺寸的特点因此有很宽的应用范围例如便携/电池供电仪表笔输入
量化器工业控制和数据/信号采集器等
本文设计了工作在 ~ V 单电源电压下典型吞吐率达 1 Msps 的 12 位
高速低功耗的逐次逼近式 A/D 转换器 D/A 转换器和比较器的性能对逐次逼近式
A/D 转换器的性能影响很大因此本文主要研究 D/A 转换器和比较器的设计只要这
两部分的设计满足一定的性能要求逐次逼近 A/D 转换器就能很好的工作
设计中 D/A 转换器采用了加电容分压器的电荷分布式结构在扩展并行 D/A 转
换器分辨率的同时大大节省了芯片面积设计的比较器结构是低增益高带宽的前置
放大器后面再紧跟一个动态锁存形式既满足了高速比较的要求又有效降低了功耗
在高分辨率的 A/D 转换设计中采样/保持电路的设计也是非常重要的本设计
采用了下极板采样技术可以有效地避免电荷注入效应引起的信号失真
仿真结果表明设计的高速比较器 D/A 转换器满足 12 位 A/D 转换的要求逐
次逼近 A/D 转换器可以正常的工作

关键词集成电路 A/D 转换器 D/A 转换器逐次逼近比较器
I
ABSTRACT
In the front and the end of the advanced electronics systems, analog to digital
converters (A/D converters) are applied to improve the performance of the digital
processing technique. Of all kinds of A/D converters, essive approximation (SAR)
A/D converters are frequently the architecture of choice for medium-to-high-resolution
applications with sample rates under 5 mega samples per second (Msps). Because of
providing low power consumption as well as a small form factor, SAR A/D converters have
a wide variety of applications, such as portable/battery-powered instrument, pen digitizers,
industrial controls and data/signal acquisition.
A 12-bit high speed, low power, SAR A/D converter is designed, which operates from
a signal V to V power supply and features throughput rates up 1Msps.
Performances of digital-analog (D/A) converters parators have a very deep
influence on SAR A/D converters, so the research of the two parts’ design is focused on. If
they can have good performances, SAR A/D converters can work well.
A charge scaling D/A converter with capacitor voltage divider is designed, which
extends the resolution of a parallel D/A converter as well as reduces the chip area greatly.
For th