8位SAR ADC设计相关问题

陳旭

请问各位大佬，对于八位sarADC，比较器使用的是一个双尾锁存型比较器。但这个比较器失调大于0.5LSB（仿出来σ≈4.8mV，我希望3σ≤7mV）
       
有什么降低失调的方法吗（除了暴力增大输入管
我看了几篇关于低失调结构比较器的论文，复现出来σ还是有二点多mV。
图二我也试了一下，失调消除电容要非常大，比较器才能工作
大佬们有什么方法嘛？可以推荐一下论文

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onepound

assuming minimum l is 180n then you could use 360n instead of 400n and increase the w therefore you would not increase the transistor area but you would increas the w/l ration by about 10% its not much but with large w/l matching is essentially vth only.

陳旭

   

onepound 发表于 2025-11-23 00:00
assuming minimum l is 180n then you could use 360n instead of 400n and increase the w therefore you  ...

Thank you, senior. I tried to set l to 180n, 360n, and increase w, but the imbalance that Mengka ran out of was still significant. Only when the input tube size is large enough, a deviation of a little over mV in σ is acceptable. However, at this point, due to the large input tube, the kick back noise deteriorates significantly
谢谢前辈。我尝试将l设成180n、360n，并增大w，蒙卡跑出来的失调仍然较大。只有输入管尺寸足够大的时候，失调的σ有一点多mV，是符合要求的。可这时由于输入管过大，回踢噪声恶化较为明显

onepound

I think working with such geometry there are limits to what you can match without calibration. you could try doubling the l on the latch though it is hard to see why that would make much difference

陳旭

   

onepound 发表于 2025-11-23 21:56
I think working with such geometry there are limits to what you can match without calibration. you c ...

Thanks for the insight. Regarding offset calibration, are there any specific techniques you would recommend? If you could point me towards some key papers or references, that would be very helpful.
谢谢前辈的回答。请问关于比较器有什么校准技术吗？可以推荐一些相关论文吗