 It is generated by a linear mechanism in resistors and FETs, but a non-linear mechanism in BJTs and diodes.The flicker-noise voltage power in MOSFET is often modeled as formula_1, where "K" is the process-dependent constant, formula_2 is the oxide capacitance in MOSFET devices, "W" and "L" are channel width and length respectively.This is an empirical model and generally thought to be an oversimplification.