A Time-Slicing Ring Oscillator for Capturing Instantaneous Delay Degradation and Power Supply Voltage Drop

A time-slicing ring oscillator (TSRO) which captures dynamic delay degradation due to instantaneous voltage drop on a power supply network is proposed. Voltage drop impact on delay is directly measured and time-domain effective voltage drop waveforms is also obtained. The TSRO consists of standard logic cells only hence fits almost anywhere in logic circuits for in-situ measurements. Measurement results of a test chip using 90-nm process successfully proved its concept