havingyu
Newbie level 2
I'm using Cadence ADE L to characterize the 1/f corner (the frequency when flicker noise is equal to drain current noise) of a single NFET with an aspect ratio of 20u/120n. I did a "noise" simulation with frequency ranging from 1 to 10THz. Then, I could see two ways to plot noise:
1. Direct plot -> Main form -> noise -> Output Noise -> plot;
2. Calculator -> vn -> select the MOS device in schematics -> select fn and id in the list popped out -> the equation in calculator will be like "VNPP("/T1","fn")" and VNPP("/T1","id") -> then plot both and find the "corner";
I did both, but neither gave me a normal result. I found my corner frequency at 250MHz for a nfet of 20u/120n using the first method! And 300MHz for the same device using the second method!
I think the normal corner frequency for a 20u/120n NFET should be around 100kHz at least, not some value in MHz. Could anyone kindly tell me where I did wrong and how to get a correct corner frequency for a single device?
1. Direct plot -> Main form -> noise -> Output Noise -> plot;
2. Calculator -> vn -> select the MOS device in schematics -> select fn and id in the list popped out -> the equation in calculator will be like "VNPP("/T1","fn")" and VNPP("/T1","id") -> then plot both and find the "corner";
I did both, but neither gave me a normal result. I found my corner frequency at 250MHz for a nfet of 20u/120n using the first method! And 300MHz for the same device using the second method!
I think the normal corner frequency for a 20u/120n NFET should be around 100kHz at least, not some value in MHz. Could anyone kindly tell me where I did wrong and how to get a correct corner frequency for a single device?