adc输入问题求助

goat_xdg

小的最近在做一个adc,要求是单端输入,据我所知,很多adc都是差分输入,这样可以消除偶次偕波,而单转双的结构都是做在adc外部的,adc有正负输入端,现在上峰要求只做一个输入端,如果仍然想使用差分信号的话,只能把单转双的结构做在adc内部,不知道有这方面的结构吗,请高人指点啊

zhfhit

Yes, as you know use diff input can improve the sndr.Usually , in your adc ,you should have a sh block, if it is differential , you can tie one port (vin) to your common mode voltage, then the other port (vip) use as your single input ,the swing should double because you are now single input. but this method sometimes will decrease your sndr ,just a trade off ,or other,you should use a strong enough s2d block.

goat_xdg

谢谢,但我不是 很明白你的意思,你是说用差分的采保吗,一端接共摸电压,一端接输入信号,这样怎么形成差分信号呢,我现在也是用的差分采保,一端接输入信号,一端接地.能在说的详细点吗,非常感谢