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This work presents the design of a 24-GHz digitally controlled oscillator (DCO) in an advanced 28-nm bulk CMOS technology for short-range frequency-modulated continuous-wave radar system-on-chip for mobile and Internet-of-Things devices. The power minimization is therefore the primary focus. The oscillator consumes a record low power of 1.2 mW at a 0.65-V supply voltage. It achieves a very large frequency tuning range (TR) of 5.8 GHz (27%) and a 150 kHz resolution without significantly degrading the phase noise (PN). The proposed design methodology results in a state-of-the-art -193 dBc/Hz FoM(T).

This paper presents a study of MOSFETs’ linearity, exploiting a simplified version of the charge-based EKV model. It allows to deduce analytically the one-tone and two-tone harmonic distortions introduced by the nonlinear $I_{D}$ – $V_{G}$ MOSFET characteristic as a function of the inversion coefficient. The short-channel effects are included in order to address nanoscale MOSFET performance. The analysis is validated through comparisons with the BSIM6 model and measurement results from 28-nm bulk CMOS devices. By means of this model, the designer can choose the appropriate bias region for the critical devices of a circuit depending on the system requirements.

This article presents the s implified charge-based Enz-Krummenacher-Vittoz (EKV) [11] metal-oxide-semiconductor field-effect transistor (MOSFET) model and shows that it can be used for advanced complementary metal-oxide-semiconductor (CMOS) processes despite its very few parameters. The concept of an inversion coefficient (IC) is first introduced as an essential design parameter that replaces the overdrive voltage VG-VT0 and spans the entire range of operating points from weak via moderate to strong inversion (SI), including the effect of velocity saturation (VS). The simplified model in saturation is then presented and validated for different 40- and 28-nm bulk CMOS processes. A very simple expression of the normalized transconductance in saturation, valid from weak to SI and requiring only the VS parameter mc, is described. The normalized transconductance efficiency Gm/ID, which is a key figure-of-merit (FoM) for the design of low-power analog circuits, is then derived as a function of IC including the effect of VS. It is then successfully validated from weak to SI with data measured on a 40-nm and two 28-nm bulk CMOS processes. It is then shown that the normalized output conductance Gds/ID follows a similar dependence with IC than the normalized Gm/ID characteristic but with different parameters accounting for drain induced barrier lowering (DIBL). The methodology for extracting the few parameters from the measured ID-VG and ID-VD characteristics is then detailed. Finally, it is shown that the simplified EKV model can also be used for a fully depleted silicon on insulator (FDSOI) and Fin-FET 28-nm processes.

This paper investigates the phase noise in LC oscillators with NMOS cross-coupled pair by means of a linear analysis. The latter includes the impact of noise sources that are often neglected, such as gate leakage shot noise, induced gate noise and all terminal access resistances noise. Despite not considering up-conversion of flicker noise, this linear analysis still provides reliable and useful results, demonstrated by means of a detailed comparison between the analytical description and simulations results from a 40nm and a 28nm CMOS technology.

This paper carries out a power-driven performance analysis on the most widely used LC oscillators' topologies, by means of the Inversion Coefficient methodology. The aim is to investigate on the best trade-off for Internet-of-Things related applications, where power consumption shall be minimized. The analysis is based on the BSIM6 model targeting a 40nm CMOS technology to investigate the trade-offs related to each topology and comparing them with respect to output voltage amplitude, phase noise and power consumption. The comparison is based on a figure-of-merit highlighting the best biasing regions, in terms of Inversion Coefficient, for the target required performance.