A power-gating array configured to power gate a logic block includes multiple zones of sleep field-effect transistors (FETs). A zone controller coupled to the power-gating array selectively enables a certain number of zones within the array depending on the voltage drawn by the logic block. When the logic block draws a lower voltage, the zone controller enables a lower number of zones. When the logic block draws a higher voltage, the zone controller enables a greater number of zones. One advantage of the disclosed technique is that sleep FET usage is reduced, thereby countering the effects of FET deterioration due to BTI and TDDB. Accordingly, the lifetime of sleep FETs configured to perform power gating for logic blocks may be extended.