baohulu
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Posts: 43
china
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I have done a mixer, its lo and input is tied together to a sinewave with large peak when it is used
but in simulation its performance, how to do the pac and pnoise accurately? I use two method: 1. I do pac & pnoise just as normal: input is connected to a port with dc type and pac setting to 1, lo is connected to a port with sinewave type and pac setting to 0, then do pss, pac & pnoise 2. just as its practical application, I connected input and lo pin together to a port with sinewave type setting its pac=1, then do pss, pac and pnoise?
the two simulations results are below: for pac: they are nearly the same for pnoise: they are totally different, I see bias noise is the largest in 2nd method, it may be because the circuit bad balance when input is large signal. in 1st method, the largest is mixer input
I know pac is a small-signal simulation method, when I connected input with a large signal as in 2nd, is the pac simulation results right? pnoise is not a small-signal simulation method, so , if the 2nd simulation is right? and the 1st simulation of pnoise not considered the linearity caused by the input large signal.
anyone knows the right simulation method when the mixer input is connected to a large signal as above?
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