Patent ID: 6927997
Filing Date: 2005-08-09
Classification: G11C

Abstract:
1. An OTP ROM cell having a first input terminal, a second input terminal and a third input terminal, wherein the OTP ROM stores data by means of a voltage applied to the first to third input terminals, the OTP ROM cell comprising: a cell access transistor having a gate forming the second input terminal, a drain and a source forming the first input terminal, wherein the cell access transistor is activated by a voltage applied to between the gate and source; a high-voltage blocking transistor having a gate, a drain and a source connected to the drain of the cell access transistor, wherein the high-voltage blocking transistor allows the current to flow from the drain to the source by means of a bias voltage applied to the gate, thus blocking the high voltage applied to the third input terminal from being directly applied to the cell access transistor; and an antifuse transistor having a gate forming the third input terminal, and a source and a drain which are connected to each other and are then connected to the drain of the high-voltage blocking transistor, wherein a high voltage is applied to the third input terminal and if the cell access transistor is activated, gate oxide is broken and shorted.