14位200MSPS三段式电流舵D／A转换器的设计

Design of 14-bit 200MSPS Three-segmented Current-steering D/A Converter

为满足现代通信系统和混合信号领域的要求,本文设计了一款14位、200MSPS的D/A转换器。通过对线性度、动态性能、功耗和面积的折中考虑并对二进制加权电流源与单位电流源的优化组合,设计采用了三段式电流舵结构。文中重点讨论了关键电路的设计,并基于SMIC 0.35μm Mixed Signal 2P3M工艺模型对电路进行了仿真验证。仿真结果表明D/A转换器的非线性误差和无杂散动态范围都达到了设计指标的要求。

A 14-bit, 200MSPS digital-to-analog converter was designed for high-performance communication systems and mixed-signal fields. Considering the trade-off among linearity, chip area, dynamic performance and power consumption, the proposed D/A converter adopts three-segmented current-steering structure to achieve optimum combination between unit current sources and binary weighted current sources. The paper focuses on the design of several key circuits. Hspice simulation verification was carried out based on the SMIC 0.35 m mixed signal 2P3M CMOS process model. Simulation results demonstrate that the nonlinear errors and SFDR of the proposed circuit meet the design requirements.