Systems and methods for a capacitive coupler for high-voltage step-down include an actively-controlled current-steering circuit connected in series with a current-limiting capacitor in order to transform a higher and potentially variable AC voltage to a lower regulated DC voltage. The actively-controlled current-steering circuit includes a switching element which, during operation, is predominantly either fully open or fully closed, and comparatively spends only a small fraction of operating time in a transition-state between the open and closed positions.