TID Sensitivity Assessment of Quadrature LC-Tank VCOs Implemented in 65-nm CMOS Technology

This article presents a comprehensive assessment of the ionizing radiation induced effects on performance quadrature phase LC-tank based voltage-controlled-oscillators (VCOs). Two different VCOs (QVCOs) that are capable generating frequencies in range 2.5 GHz to 2.9 implemented commercial 65 nm bulk CMOS technology target for harsh environments like space applications and high-energy physics (HEP) experiments. Each QVCOs consumes 13 mW power from 1.2 V supply. The architectures popular implementation two types QVCOs: parallel-coupled QVCO (PQVCO) super-harmonic coupled (SQVCO). various metrics (oscillation frequency, phase, noise, frequency tuning range, consumption) evaluated with respect Total Dose (TID) up level approximately 100 Mrad (SiO2) through X-ray irradiation. During irradiation, electrical characterization samples prototype performed under biased condition at room temperature. Before (PQVCO SQVCO) achieve noise equal −115 dBc/Hz −119 1 MHz offset, resulting figure-of-merit (FoM) −172.2 −176.4 respectively. test-setup TID experiment is discussed results obtained statistically analyzed this perform comparative study evaluate effectiveness hardened by design techniques (RHBDs) employed implementations. Post-irradiation, overall variations oscillators less than 1% change (TR) 5% as observed tested samples.