一种基于电流输出DAC的逐次逼近A/D转换器  

A Successive Approximation Analog-to-Digital Converter Based on Current Output DAC

作　　者：温玉[1] 舒辉然[1] 高炜琪[1] 李遥[1] 

机构地区：[1]中国电子科技集团公司第二十四研究所,重庆400060

出　　处：《微电子学》2008年第6期835-838,共4页Microelectronics

摘　　要：设计了一种12位逐次逼近A/D转换器。该A/D转换器具有四种信号输入范围,利用电阻网络使不同量程的模拟输入与内部DAC输出范围保持一致,从而使用相同的比较器和基准实现对不同范围输入信号的A/D转换;采用一种新型分段电流源结构,利用电流信号实现内部DAC及逐次比较功能。该电路采用2μm LC^2MOS工艺实现,其积分线性误差(INL)和微分线性误差(DNL)为±1/2 LSB,最大转换时间为12μs。A 12-bit successive approximation A/D converter with 4 input ranges was presented. In this converter, resistor network was used to keep input signals in line with the output range of the built-in DAC, so that analog-todigital conversion for input signals in different ranges could be realized by using the same comparator and reference, and the function of DAC and successive approximation was achieved by using a new segmented current source array. Fabricated in 2μm LCZMOS process, the A/D converter has a conversion rate of 12 μs. Both INL and DNL of the device are ±1/2 LSB.

关 键 词：A/D转换器 逐次逼近 电流输出D/A转换器 

分 类 号：TN792[电子电信—电路与系统]