KD494
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Hey all,
I've done noise analysis on several signal paths now both measured with a spectrum analyzer and simulate in LTspice. I either measure or calculate the output noise in the units of nV/sqrt(Hz) and then refer it to the input by backing out the gain of the path. Only issue now is I'm working with a fully differential circuit so the output has two different legs.
I'm trying to first simulate the circuit but I'm having trouble deciding where to place the input source. Should it be between the inputs or from an individual input to ground? LTspice also only wants me to select one node as the output. Again, should I measure the output noise on each of the legs? I feel like there must be someway to combine them into one number like a single ended equivalent noise but I'm not sure what that would be. Let me know if I can provide anymore detail, this has been bugging me for a while now.
Thanks.
I've done noise analysis on several signal paths now both measured with a spectrum analyzer and simulate in LTspice. I either measure or calculate the output noise in the units of nV/sqrt(Hz) and then refer it to the input by backing out the gain of the path. Only issue now is I'm working with a fully differential circuit so the output has two different legs.
I'm trying to first simulate the circuit but I'm having trouble deciding where to place the input source. Should it be between the inputs or from an individual input to ground? LTspice also only wants me to select one node as the output. Again, should I measure the output noise on each of the legs? I feel like there must be someway to combine them into one number like a single ended equivalent noise but I'm not sure what that would be. Let me know if I can provide anymore detail, this has been bugging me for a while now.
Thanks.
