An apparatus is provided, which includes energy storage circuitry to store energy and to supply some of the energy to the apparatus. Discharge circuitry discharges the energy storage circuitry in response to the energy being supplied to the apparatus. Power supply circuitry recharges the energy storage circuitry. The discharge circuitry retains a non-zero residual energy in the energy storage circuitry when the energy storage circuitry is discharged by the discharge circuitry.