An on-chip monitor for statistically significant circuit aging characterization

We present an array-based system to accurately study variations in ROSC aging. Microsecond measurements for minimal BTI recovery, and frequency shift measurement resolution ranging down to the error floor of 0.07% are achieved with three beat frequency detection systems working in tandem. Measurement results from a 65nm test chip show that fresh frequency and Δf are uncorrelated, both the μ and σ of Δf increase with stress, and σ(Δf)/μ(Δf) decreases with stress time.