A delay circuit receives a data input having an input transition and that generates a data output having an output transition. The delay circuit is powered by a voltage source having a voltage. A first delay element is configured to generate a first data signal with a first edge that has a relatively constant delay relative to the input transition irrespective of the voltage of the voltage source. A second delay element is configured to generate a second data signal with a second edge that has a delay relative to the input transition as a function of the voltage of the voltage source. A selection element causes the output transition at the data output to correspond to a latest selected one of the first edge and the second edge. The delay circuit may be employed in a pulse generating circuit.