Jacki
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Hello,
I want to design a switched-capacitor amplifier (SC-amplifier), but the noise spec is not integrated noise. It is noise figure (3dB). The input source resistor is 1kohms.
I am familiar with LNA and mixer NF simulation. But for the SC-amplifier, I don't know how to simulate the NF. For my own opinion, NF is a kind frequency spectrum sweep. But for SC-amplifier, it is integrated noise. How to equalize these two concepts?
Also, I try PNoise simulation in Spectre, a very strange thing happens, when I reduce the source resistor value from 1kohms to 50ohms, the NF increases.
Anybody can give me some hints?
Thank you very much!
Jacki
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