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I am learning to design circuits using gm/ID lookup tables and I now try to design Miller OTA but I am no sure how to start. I have set myself parameters that I should strife to like: GBW, SR, CL. I first start with determining:
\[ C_S = 0.22C_L \]
\[ gm_{m12} =2\pi GBW C_L \]
Here is my first concern because I need to split the gain in both stages and obviously they won't be the same. The first stage should be with higher. And they both won't be with the same fp. But for now I tried calculating with GBW. At the start of the design I choose length and gm/ID of all transistors for example:
\[ gmID_{m12}=12,gmID_{m34}=6, gmID_{m5}=gmID_{m7}=6,gmID{m6}=12 \]
Using them I can calculate the currents. Using lookup tables I can compute JD and find the W. But I know I am far away from the right answer because I know that the power of lookup tables is that like I can make graph of gain, bw etc. and optimize the circuit by interpolating etc. But I think am still new and don't know hot to do it. Does someone has suggestion or graphs I should make of the OTA to help me design? (For clarification I have the basic graphs of the transistors like gm/ID vs VGS, fT, A0, JD and more, I am looking for graphs on the OTA)
\[ C_S = 0.22C_L \]
\[ gm_{m12} =2\pi GBW C_L \]
Here is my first concern because I need to split the gain in both stages and obviously they won't be the same. The first stage should be with higher. And they both won't be with the same fp. But for now I tried calculating with GBW. At the start of the design I choose length and gm/ID of all transistors for example:
\[ gmID_{m12}=12,gmID_{m34}=6, gmID_{m5}=gmID_{m7}=6,gmID{m6}=12 \]
Using them I can calculate the currents. Using lookup tables I can compute JD and find the W. But I know I am far away from the right answer because I know that the power of lookup tables is that like I can make graph of gain, bw etc. and optimize the circuit by interpolating etc. But I think am still new and don't know hot to do it. Does someone has suggestion or graphs I should make of the OTA to help me design? (For clarification I have the basic graphs of the transistors like gm/ID vs VGS, fT, A0, JD and more, I am looking for graphs on the OTA)
