Improving the quality factor estimation for differentially driven RF CMOS inductor

The quality factor of on-chip differentially driven RF CMOS inductors is derived using energy based formulas from an equivalent differential one-port model for the inductor, taking into account the influence of signal leakage to ground at high frequencies. The quality factor is calculated for various load conditions and compared to published results based on existing definitions of the quality factor. Results suggest that both differential and common mode signals have to be taken into account for an accurate estimation of the quality factor.