Determination of transconductance-to-drain-current dependent flicker noise parameters

Previous studies have shown that the transconductance-to-drain-current ratio (gm/ID) based technique is useful for noise analysis and optimization of analog CMOS circuits. In this paper, we examine flicker noise closely and show that even though its slope (A) does not depend gm/ID parameters of a transistor, knowledge of gm/ID parameters is required in order to determine its slope accurately. We take a look at several scenarios that arise in practice, and generate a simple rule of thumb that simplifies the process of de-embedding the slope of flicker noise. Finally, we apply the results in the analysis of a micropower operational transconductance amplifier (OTA) and show that excellent agreement between simulation and analysis is achieved.