Low frequency noise has been studied from the weak to strong inversion regime in n-channel MOS transistors. The 1/f current noise power spectrum density S-ID is measured as a function of the drain current and gate voltage with the gate length as a parameter. Analysis of the noise characteristics shows that the channel noise agrees with the mobility fluctuation model and can be predicted in the linear and saturation region using the H parameter only. Finally, the three parameters NOIA, NOIB and NOIC used in the BSIM3v3 noise model are extracted. Some discrepancies of the noise simulation with the experimental data are observed. (C) 2002 Elsevier Science Ltd. All rights reserved.