On-chip circuit for measuring multi-GHz clock signal waveforms

An on-chip circuit to measure full analog waveforms of internal signals is described. It can measure signals up to a repetition rate of at least 7 GHz, a bandwidth of at least 12 GHz, with accuracy required to detect subtle differences in signals, and it can measure overshoot above the rail voltage. It has been demonstrated on an experimental clock grid with optional resonant operation.