System and method for measuring circuit performance degradation due to PFET negative bias temperature instability (NBTI)

摘要

A ring oscillator (and test circuit incorporating the ring oscillator and test method therefor) includes an odd number of elements interconnected in a serially-connected infinite loop, each oscillator element having an associated programmable delay feature. The circuit can be used to measure effects of Negative Bias Temperature Instability (NBTI) in p-channel MOSFETs (PFETs).