Title :
Figure-of-merit for optimizing the current-efficiency of low-power RF circuits
Author :
Mangla, A. ; Enz, C.C. ; Sallese, J.M.
Author_Institution :
Ecole Polytech. Fed. de Lausanne (EPFL), Lausanne, Switzerland
Abstract :
The widely used RF Figures-of-Merit such as transit frequency (ft) and maximum frequency of oscillation (fmax), are only partial measures of performance and not well adapted to ultra-low power RF design. These FoMs are narrowly defined to characterize the speed of operation but without any consideration about the power efficiency of the device. A new FoM comprising both, the current-efficiency and the ability of the device to show gain at RF has been defined. This FoM lends itself naturally for the optimization of the operating points of RF circuits. In this paper we derive analytical expressions for ID and Gm, continuous from weak inversion to strong inversion and including velocity saturation, to evaluate the FoM. We extract the value of a critical inversion coefficient Icrit as the theoretical edge between velocity saturation and non-velocity saturation regions and show that the FoM has a peak which lies in the moderate inversion region at equation.
Keywords :
circuit oscillations; integrated circuit design; low-power electronics; radiofrequency integrated circuits; critical inversion coefficient; current efficiency; figure of merit; maximum frequency of oscillation; transit frequency; ultra low power RF design; velocity saturation; Current measurement; Integrated circuit modeling; Logic gates; Radio frequency; Semiconductor device modeling; Transistors; RF integrated circuit design; figure-of-merit; inversion coefficient; low power; moderate inversion; transconductance; transit frequency; velocity saturation;
Conference_Titel :
Mixed Design of Integrated Circuits and Systems (MIXDES), 2011 Proceedings of the 18th International Conference
Conference_Location :
Gliwice
Print_ISBN :
978-1-4577-0304-1
