Broadband opamps for multi-channel communication systems have strong demands on linearity performance. When these opamps are integrated in deep sub-micron CMOS technologies, the signal-swing has to occupy a large part of the rather low supply voltage to maintain the signal-to-noise-ratio. To obtain opamps with low distortion it is necessary to do a thorough analysis of the nonlinear behaviour of such circuits and this is the main subject of Design Criteria for Low Distortion in Feedback Opamp Circuits..