Dynamic Supply Noise Measurement with All Digital Gated Oscillator for Evaluating Decoupling Capacitance Effect

This paper proposes an all digital measurement circuit called "gated oscillator" for capturing waveforms of dynamic power supply noise. The gated oscillator is constructed with standard cells, and thus easily embedded in SoCs. The performance of the gated oscillator is testified with fabricated test chips in a 90 nm process. Characteristics of decoupling capacitance are discussed focusing on channel length and distance, based on supply noise waveforms measured by the gated oscillator.