Fast and Accurate Phase Noise Analysis of Crystal Oscillator in 28 FDSOI Process
DescriptionThe Phase Lock Loop(PLL) is a critical component for any receiver system. Crystal(XTAL) Oscillator is important as it acts as the reference for the PLL, thus best phase noise is targeted for the XTAL Oscillator. Due to HighQ & very low noise levels of the XTAL, computation of phase noise accurately is a challenge.
Harmonic-Balance(HB) analysis which is a frequency-domain analysis is required to detect the steady-state of the oscillator and measure the phase-noise. Major challenges with existing solutions are multiple explicit simulator settings, longer simulation time and convergence issues.
To address these challenges, we have used Spectre-XRF simulator which is using Spectre-X technology to run HB analysis. Spectre-XRF offers a simple single-preset use-model which eliminates the need of explicitly setting the simulation options and provides significant performance gain while maintaining the spice accuracy.
In this paper, we have achieved close to silicon accuracy using Spectre-XRF with 2X performance gain as compared to existing solution. With +preset=ax mode, the phase noise measurement at 1MHz frequency offset is -174.37dBc/Hz for SSB. For the same 1MHz frequency offset, the silicon reference number is -170.33dBc/Hz. Using Virtuoso ADE-Assembler-Spectre-XRF flow, the overall design cycle was reduced by 30% as compared to existing command-line flow.
TimeTuesday, July 11th2:30pm - 2:45pm PDT
Location2012, 2nd Floor