摘要 |
A single pull-up circuit is shared between a redundant row antifuse cell, and a redundant column antifuse cell. Additionally, a single selection circuit is shared between the two antifuse cells. A row selection signal supplied thereto selects the antifuse cell for the redundant row, while a column selection signal selects the antifuse cell for the redundant column. A small channel length transistor is employed within the latch circuit. As a result, the latch can quickly pull up a value when the antifuse cell is not blown, and quickly latch that value within the latch since an RC time constant of the latch is decreased. A pulsed pull-up signal having a very short duration is employed to enable the latch. Since the pulsed pull-up signal has a short duration, a high voltage supply VCC is provided through the latch and a blown antifuse cell to ground for only a short duration, thereby minimizing the possibility of such a low resistance current path from damaging the circuitry. A transistor having a large channel resistance, however, is placed within a feedback path of the latch. Therefore, after the latch is set, if the antifuse cell is blown, the high resistance transistor provides a resistive current path from the VCC to ground.
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