数模混合信号前端的系统分割考虑ADI

简介：

问：MxFE是否包含PLL?
答： Some MxFE has the PLL, but the clock cannot be used externally. For example, AD9861 has it. All these information can be got from their datasheets.

问：MxFE的内置滤波器是用什么方式实现的？
使用时是否要外交部LC？
答： The integrated filter are digital filters. No external LC will be needed. You can refer to the datasheets of them www.analog.com

问：AD9851有幅度调制寄存器吗？
答： AD9851没有幅度调制寄存器

问：不同频率的模拟信号需要地线分割吗?
答： It"s a concept of "shielding" with grounding line. For high frequency signal it"s necessary.

问：混合使用IC集成系统和使用SOC集成系统成本上好像还是有很大差异，比如使用内置的TV－encoder和外部的TVencoder之间就有可观的成本。有否一个可行的计算方法，考虑这个成本？

答： When we talked today about system partition, we mainly focus on AFE. You question is a little different from this topic. Basically, using internal encoder can be cost effective (but depending on application market data, like volume, technology mature statu

问：随着便携式系统和混合电平器件的增加，为了降低功耗、分离模拟地和数字地、减少PCB层数，PCB设计中大量采用了地电平面的分割。但是，地电平面的分割会导致共模噪声的增加,请问如何可以减少EMI噪声?
答： Your question is not so clear, however, ground spliting can help to decrease grounding noise i/o increase it.
For common noise like grounding noise, you can use differential amp to reject noise; for EMI, "shielding" is a good way, but proper

问：使用9862 常出现的错误请举出2例
答： We have not encountered problems in using AD9862. Feel free to use it, and we can provide technical support locally. The toll-free number 800 810 is one way for you.

问：模拟电源的低通滤波器如何设计?通带的宽度有什么来确定?阻带衰耗多大合适?
答： Normally it"s not filter for power supply, but only de-coupling with like capacitors. If you"re using single supply for both analog and digital circuit, then please use ferrite-bead between digital and analog power supply pin of the IC.

问：Eagle,
each MxFE is designed to special solution,does it mean s if I use it to other will waste  parts of the function and the cost will be high?
答： While its true that MxFEs are targeted at specific functions, they are designed to be flexible. By designing them for multiple functions, the volume is high, so the cost is low. The pricing of MxFEs is designed so that even if not all functions are used, t

问：What"s the goldedn rule for signal shielding based on frequency?

答： Please notice the seperation of analog circuit and digital circuit. Please notice the power supply and ground design. For high frequency design,please use shielder.