数模转换器(DAC)的基本原理ADI

简介：

问：比如做超声波通信，就是有两个终端，分别进行发送和接收，那么发送端的DA的精度是不是要比接收端的AD的精度要高，如DA要14bit的，AD只需12bit的，同时DA的频率是不是要比AD高10倍左右？谢谢。
答： It depends on you system. For the ADC, please consider your sentivity (AD6644 is 14 bit, AD9226 is 12bit. Please note 3db sentivity lower will cause half in receive distance).
Normally use our TXDAC (for example, AD9777, 16-Bit Resolution, 160/400 MSPS

问：我的系统需要4通道通过率在200k以上的DAC，并且希望是并口或IIC，AD公司对此有什么解决方案？
答： You can use AD5583(10bit 4 channel, parallel port) or AD5344 (2.5 V to 5.5 V Parallel Interface 4 channel DAC).

问：请介绍一下DAC在软件无线电中的应用
答： The key advantage in software is that there is no need to change your hardware when you change protocol.
For example, for the transimiter, use ADSP-TS101 DSP -> AD6623 (4 channel upconverter) -> AD7772A(14bit 160 MSPS TxDAC ) or AD9777 (16bit 16

问：在进行AD/DA时，外部时钟如何控制转换？时钟的准确度如何影响转换？
答： OK, for the ADC, there will be pin for the start conversion and the end of conversion. But for the DAC, only use the start conversion controlled by the processor.

For the clock that influence the resolution, refer to the datasheet of AD6644, there

问：請提供貴公司在深圳的代理商的聯絡方式,OK?
答： Chiantronic(华创）0755-83781886
excelpoint 83640166
arrow 83592920
future 82090239
wpg 83580555

问：多通道dac地线处理以及非线性误差处理如何实现?
答： Just use a large area ground in your board, then connect the digital ground and analog ground together in one point.

For the nonlinear errors, you cannot process it. It is decided by the DAC itself. Maybe you can consider calibrate in your system

问：补充一下，我的系统需要4通道，12位或14位，通过率在200k以上的DAC，并且希望是并口或IIC，AD公司对此有什么解决方案？

答： Pls. ref next parts datasheet: 12bit parall interface AD5283; 14 bit parallel interface AD7835/36. More parts find at www.analog.com

问：1.能否介绍一下sigma-delta原理的DAC和ADC?
2.前一次的ADC讲座我错过了，能否得到相应的资料？
答： Hi all of the principles of the Sigma-delta was given on the seminar. For more details, you need to read some other books. For the seminar file last time, please offer your email address and city where you"re in, then either you can contact with our d

问：能否谈一下DAC做电子分压器的使用方法？谢谢
答： We have a separate line of Digital Potentiometers (DigiPOT) which are basically derived off from DAC technology.  DigiPOT however offers more "special" functions.  For example, there is "set and forget" type of Digit

问：当用DAC做分压器使用时与DIGITAL POT相比有什么差异？谢谢
答： DAC have high resolutions,but low voltage for Vref.
Digital POT have wide dynamic input(positive,negative voltage),more features for easy use like power on midscale,nonvolative memory etc.