Control circuits that employ time-based current control methods for switching voltage regulators are provided. The control circuit includes a current estimation circuit and optionally, a transfer function circuit. The current estimation circuit generates estimates of regulator output current as function of switch period for use as a threshold indicative of peak current limit. This arrangement eliminates the need for error amplifiers to provide effective current mode control. The absence of error amplifiers allows fabrication of switching regulators on smaller die areas and provides switching regulators with reduced power consumption.