Method and ring oscillator for evaluating dynamic circuits

The present invention relates generally to oscillator circuits, and more particularly, relates to a ring oscillator and methods for evaluating dynamic circuits. Measurement methods and a ring oscillator circuit are provided for evaluating dynamic circuits. The ring oscillator circuit includes a one-shot pulse generator receiving a single transition input signal and producing a pulse output signal having a rising transition and falling transition. The dynamic circuit to be evaluated is coupled to an output of the one-shot pulse generator receiving the pulse output signal of the one-shot pulse generator and producing a delayed output pulse at an output. A divide-by-two circuit is coupled to the output of the dynamic circuit to be evaluated. An output signal of the divide-by-two circuit is fed back to the one-shot pulse generator, and the cycle is repeated, thus oscillating. A multiplexer is connected between output of the dynamic circuit to be evaluated and the divide-by-two circuit. The multiplexer receives the pulse output of the one-shot pulse generator and includes a select input for selecting the output of the dynamic circuit to be evaluated or the pulse output of the one-shot pulse generator. By inserting the evaluation circuit into a path that can be multiplexed in and out of the oscillator path, and by measuring the difference between the frequency with and without the evaluation circuit in the path, the performance of the evaluation circuit can be accurately determined.