Low 1/f3 Noise Corner LC-VCO Design Using Flicker Noise Filtering Technique in 22nm FD-SOI

Abstract

This paper presents a K/Ka-band voltage biased differential LC-VCO in 22nm FD-SOI achieving a 1/f 3 corner below 18 kHz and a figure-of-merit (FOM) at 1 MHz offset frequency of 188~190 dBc/Hz over the tuning range. Thanks to the flicker noise filtering technique, flicker noise upconversion can be suppressed significantly without degrading the phase noise (PN) in the 1/f 2 region. The difference in connection of the switched-capacitor bank (SCB) over the VCO tuning range is taken into account in our analysis of flicker noise filtering. The VCO uses differential source degeneration with a self-coupled inductor that is used for layout compactness and common-mode (CM) resonance manipulation. To obtain a low 1/f 3 corner over the tuning range, a common centroid layout technique is used for the SCB. The post-layout simulation shows that the 1/f 3 corner is well below 50 kHz over the tuning range in different process corners. The PN@1 MHz and PN@100 kHz are -110.2 dBc/Hz and -89.9 dBc/Hz, respectively, at the center of the tuning range with a power consumption of 8.8 mW.