Abstract: Methods and apparatus are provided for on-chip signal waveform measurement. An integrated circuit is provided that comprises an on-chip comparator for comparing a voltage level of a signal to be measured to a voltage level of a reference voltage, at a time determined by at least one edge of an evaluation clock. The reference voltage can be varied to obtain a plurality of voltage points. The evaluation clock can be varied to obtain a plurality of time sampling points. In addition, the reference voltage and the evaluation clock can both be varied to obtain a plurality of voltage-time sampling points constituting a waveform corresponding to the signal to be measured.