Design and Performance Analysis of a 9-Stage CMOS Ring Oscillator at 2.4 GHz

Abstract

The rapid development of wireless communication systems operating in the 2,4 GHz frequency band, such as Wi-Fi, Bluetooth, and the Internet of Things (IoT), has increased the demand for low-power frequency generators that can be easily integrated using Complementary Metal-Oxide-Semiconductor (CMOS) technology. This paper presents the design and analysis of a 9-stage ring oscillator based on 45 nm CMOS technology as a frequency generator for integrated wireless applications. The circuit is designed at the transistor level using CMOS inverters with an odd number of stages, while its performance is evaluated through transient simulation and frequency spectrum analysis. Simulations are carried out using Electric as the integrated circuit design tool and LTspice as a SPICE-based circuit simulator. Simulation results show that the proposed ring oscillator achieves stable oscillation at a frequency of 2,44 GHz with a supply voltage of 1,0 V. Power consumption analysis indicates an average power dissipation of 254 µW under steady-state operation. The design efficiency is evaluated using a power-frequency-based Figure of Merit (FoM), yielding a FoM value of 9,61 GHz/mW. These results demonstrate that the proposed 9-stage 45 nm CMOS ring oscillator exhibits competitive power efficiency and is suitable for low-power integrated wireless systems, particularly for IoT applications and battery-powered devices.

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Issue

Vol. 8 No. 2 (2026): Jurnal Teknik Elektro dan Komputasi (ELKOM)

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