Asymmetric 5.5 GHz Three-Stage Voltage-Controlled Ring-Oscillator in 65 nm CMOS Technology

Abstract

The current trend of increasing the complexity of hardware accelerators to improve their functionality is highlighting the problem of sharing a high-frequency clock signal for all integrated modules. As the clock itself is becoming the main limitation to the performance of accelerators, in this manuscript, we present the design of an asymmetric Ring Oscillator-Voltage-Controlled Oscillator (RO-VCO) based on the Current Mode Logic architecture. The RO-VCO was designed on commercial-grade 65 nm CMOS technology, and it is capable of driving large capacitance loads, avoiding the need for additional buffers for clock-trees, reducing the silicon area and power consumption. The proposed RO-VCO is composed of three closed-loop differential and asymmetrical stages, and it is able to tune the working frequency in the range from 4.72 GHz to 6.12 GHz. The phase noise and a figure of merit of −103.2 dBc/Hz and −186 dBc/Hz were obtained at 1 MHz offset from the 5.5 GHz carrier. In this article, the analytical model, full custom schematic, and layout of the proposed RO-VCO are presented and discussed in detail together with the experimental electrical and thermal characterization of the fabricated device.

Design and Study the Performance of a CMOS-Based Ring Oscillator Architecture for 5G Mobile Communication

“…All radio communication relies on the operation of a VCO; thus, it requires the right specs and design. Ciarpi et al [28] showcased that RO-VCO exhibits a frequency tuning range spanning from 4.72 GHz to 6.12 GHz. The structure consists of three closed-loop differential stages that are asymmetrical.…”

Design and analysis of 7-stage MOS current mode logic power gated MOSFETs in current starved voltage-controlled oscillator for the phase locked loop application

“…In this, most updated M-PHY serial interface is used for high speed operation but it affects with maximum phase noise [27]. A new three stage oscillator is designed to achieve better oscillation frequency [28]. A differential CMOS ring VCO is designed with low noise for short range application, but it achieves only less frequency tuning range [29].…”