Control circuits for a voltage regulator of a semiconductor memory device include an option fuse circuit and a fusing control circuit. The option fuse circuit includes a plurality of fuses and a selection circuit that selects one of the plurality of fuses responsive to a control signal. An output voltage associated with the voltage reset circuit is adjusted responsive to a state of the selected one of the plurality of fuses. A fusing control circuit generates the control signal to allow multiple adjustments of the output voltage by the voltage reset circuit. The option fuse circuit may be a plurality of option fuse circuits and the output voltage may be adjusted responsive to the states of the respective selected ones of the plurality of fuses of the option fuse circuits.