自适应模数、数模转换器的毕业设计简析.doc

毕业设计 自适应模数/数模转换器的设计 摘　　要 随着SOC和混合信号集成电路的发展，对于芯片中数字部分与模拟部分接口电路的研究显得尤为重要。在数字和模拟领域的接口研究中，数模转换器和模数转换器的应用不仅仅局限于听觉通路——如麦克风和扩音器，视觉通路——如照相机和其他一些显示设备，而且在有线或无线通道数据传输中也有很重要的用途。典型的如数据信号依据某种机制被调制到载波上，和载波一起在有线或无线的通道中传输，接收器接收到信号再进行解调，可根据应用和可行性的不同在数字或模拟领域中解调，其应用之广泛可见一斑。 在高速数据转换电路中，速度、精度、功耗和芯片面积是四个关键的性能指标。它们之间并非独立的，而是存在相互联系、相互制约的辨证关系。任何设计都要根据具体的要求在这四个方面进行折衷。 本文主要介绍了10位，100兆采样速率的电流型数模转换器的设计和仿真。本文设计的数模转换器采用“6+2+2”的分割结构——高6位和中间2位采用相互独立的温度计译码，低2位采用二进制编码。通过锁存器产生同步的开关控制信号来控制核心转换电路的开关管，从而控制流经输出端负载电阻的电流总量，达到将输入的数字信号转换为输出模拟电压的目的。本文设计的数模转换器的特点是采用了分段编码的形式，使毛刺（glitch）误差减小，成功地将最大毛刺（glitch）抖动能量控制在0.436pV i s。另外，电流源采用共源共栅的结构提高了转换精度。 关键词: DAC；分割结构；温度计编码；二进制编码；锁存器 Adaptive modules/digital-to-analog converters design ABSTRACT With the development of SOC and mixed-signal circuits, the research on the interfaces between the digital and analog domains becomes more and more important. Within these interfaces,we find the analog-to-digital converter (ADC) and digital- to-analog converter(DAC). These data converters are not only used for conversion of audio via microphone or loudspeakers, video via camera or display, into information that the computer or digital signal processor (DSP) can handle. The data converters are also used for data transmission via a channel, where the channel is either wireline or wireless (radio). Typically, the data (signal) is modulated onto a carrier according to some scheme. The signal is then sent over the channel with the carrier. The receiver will demodulate and extract the data (signal). The modulation can be done in both the digital and analog domain dependent on application and feasibility. In high-speed data conversion circuit, speed, accuracy, power dissipation and chip area are four key performance specifications. They are not independent; instead, they are interrelated and limit each other. There is always a trade-off among these four aspects. This thesis mainly focuses on the design and simulation of the 10-bit 100MSamp