Hi Guys,
         I was simulating a multi-bit sig del Modulator. I notice that when I introduce the non linearity in the DAC (by delibrately adding mismatch in the DAC caps)then besides the appearance of  harmonic dist the noise floor of the output of the Modulator, in the baseband, goes up significantly.
What could cause this?.  I did the sim in matlab first and then in cadence/spectre. The result is the same in both .
        Any interesting ideas?
        Thanks for your time.