Nonlinearity analysis in CMOS triode transconductor at low and high frequency

In this paper nonlinearity of triode transconductor (TC) based on Taylor series at low frequency and Volterra series at high frequency are presented. Unfortunately, Taylor series does not predict the frequency-dependent linearity degradation due to parasitic capacitors. Frequency dependence nonlinearity analysis in this structure gives more intuition about distortion mechanism that necessary for properly design linearized TO at high frequency. In this paper, we present a frequency-dependent harmonic-distortion and intermoulation-distiortion analytical method applied to triode cascode TC. Analytical results are compared with simulation results and the effects of circuit parameters and frequency on linearity of triode cascade TO are formulated.