12位200MHz电流舵型DAC的设计
发布时间：2018-11-03 08:06
【摘要】：数模转换器(Digital-to-Analog Converter,简称DAC)是数字电路和模拟电路的重要接口。随着数字技术的快速提升,处理数字信号的速度越来越快,这就迫切的要求数模转换器高速高精度。 本文通过研究DAC的基本原理和基本结构,并分析每种结构的优缺点,然后按照由上到下全定制的方法设计了一个12位200MHz电流舵型数模转换器。本文所设计的DAC主要包括寄存器、译码电路、限幅电路、电流源及开关阵列、偏置电路。本文重点介绍了偏置电路中的带隙基准电路、电压-电流转换电路和运算放大器的设计原理及方法,仿真分析了带隙基准电路的温漂系数和电源抑制比和运算放大器的增益、相位裕度和带宽。本论文还分析了电流源失配对DAC的SFDR的影响并确定了电流源尺寸,并设计了一个开关控制信号的限幅电路,分析了降低时钟馈通的原理。本文还着重分析了高六位所对应电流源阵列的版图布局,设计了译码电路中行列温度计译码的选通电路,并对数字电路中寄存器、锁存器进行了仿真分析。 本文基于SMIC0.18μm工艺,利用Cadence Specter仿真工具设计了一个电源电压为3.3V,满偏电流为20mA,二进制码和温度计码分段译码方式的]2位200MHz电流舵型数模转换器(DAC)。在此电路中设计了高频下具有高输出阻抗的PMOS共源共栅电流源,从而保证了电路具有良好的SFDR。高位电流源版图采用了O2Random Walk布局方式来尽量减少因版图布局引起的误差。在信号频率0.999876MHz,采样频率200MHz情况下SFDR仿真结果超过77dB。
[Abstract]:Digital to analog converter (Digital-to-Analog Converter,) is an important interface between digital circuit and analog circuit. With the rapid development of digital technology, the speed of digital signal processing is getting faster and faster. In this paper, the basic principle and structure of DAC are studied, and the advantages and disadvantages of each structure are analyzed. Then a 12-bit 200MHz current-rudder digital-to-analog converter is designed according to the method of top-down customization. The DAC designed in this paper mainly includes register, decoding circuit, limiting circuit, current source and switch array, bias circuit. This paper mainly introduces the design principle and method of bandgap reference circuit, voltage-current conversion circuit and operational amplifier in bias circuit. The temperature drift coefficient, power rejection ratio and gain of operational amplifier of bandgap reference circuit are simulated and analyzed. Phase margin and bandwidth. In this paper, the effect of current source mismatch on SFDR of DAC is analyzed and the size of current source is determined. A limiting circuit of switch control signal is designed, and the principle of reducing clock feedthrough is analyzed. In this paper, the layout of the current source array is analyzed, and the on-off circuit of the column thermometer decoding in the decoding circuit is designed, and the register and latch in the digital circuit are simulated and analyzed. Based on SMIC0.18 渭 m technology and Cadence Specter simulation tool, a 2-bit 200MHz current-rudder digital-to-analog converter (DAC).) with 3.3V power supply voltage, 20mA full bias current, binary code and thermometer code is designed in this paper. In this circuit, a high frequency PMOS source with high output impedance is designed, which ensures that the circuit has a good SFDR.. The high current source layout adopts O2Random Walk layout to minimize the error caused by layout. When the signal frequency is 0.999876MHz and the sampling frequency is 200MHz, the simulation result of SFDR exceeds 77dB.
【学位授予单位】：北方工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN792
本文编号：2307203
[Abstract]:Digital to analog converter (Digital-to-Analog Converter,) is an important interface between digital circuit and analog circuit. With the rapid development of digital technology, the speed of digital signal processing is getting faster and faster. In this paper, the basic principle and structure of DAC are studied, and the advantages and disadvantages of each structure are analyzed. Then a 12-bit 200MHz current-rudder digital-to-analog converter is designed according to the method of top-down customization. The DAC designed in this paper mainly includes register, decoding circuit, limiting circuit, current source and switch array, bias circuit. This paper mainly introduces the design principle and method of bandgap reference circuit, voltage-current conversion circuit and operational amplifier in bias circuit. The temperature drift coefficient, power rejection ratio and gain of operational amplifier of bandgap reference circuit are simulated and analyzed. Phase margin and bandwidth. In this paper, the effect of current source mismatch on SFDR of DAC is analyzed and the size of current source is determined. A limiting circuit of switch control signal is designed, and the principle of reducing clock feedthrough is analyzed. In this paper, the layout of the current source array is analyzed, and the on-off circuit of the column thermometer decoding in the decoding circuit is designed, and the register and latch in the digital circuit are simulated and analyzed. Based on SMIC0.18 渭 m technology and Cadence Specter simulation tool, a 2-bit 200MHz current-rudder digital-to-analog converter (DAC).) with 3.3V power supply voltage, 20mA full bias current, binary code and thermometer code is designed in this paper. In this circuit, a high frequency PMOS source with high output impedance is designed, which ensures that the circuit has a good SFDR.. The high current source layout adopts O2Random Walk layout to minimize the error caused by layout. When the signal frequency is 0.999876MHz and the sampling frequency is 200MHz, the simulation result of SFDR exceeds 77dB.
【学位授予单位】：北方工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN792
【参考文献】
相关期刊论文 前1条
1 朱樟明;李亚妮;杨银堂;;一种1.8V 10位120MS/s CMOS电流舵D/A转换器IP核[J];半导体学报;2008年03期
，本文编号：2307203
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