Electronic memory.

摘要

A four device cell is disclosed for an electrically erasable programmable logic device. The four devices include a floating gate tunnel capacitor, a floating gate read transistor having its floating gate and control gate connected respectively to the floating gate and control gate of the tunnel capacitor, a read select transistor for selectively coupling the drain of the floating gate read transistor to a product term output in response to an input term, and a write select transistor for selectively coupling the drain of the floating gate tunnel capacitor to a write data line in response to the signal on a write select line. During sensing, the control gates of all the floating gate tunnel capacitors are kept at a constant voltage V<Sub>c</Sub>g. The drains of all of the floating gate tunnel capacitors are also kept at a constant voltage V<Sub>WDL </Sub>chosen to minimize read disturb on the tunnel capacitor. Preferably V<Sub>WDL</Sub> = V<Sub>c</Sub>g. V<Sub>WDL</Sub> is applied to the drain of the floating gate tunnel capacitor by applying V<Sub>WDL</Sub> to all the write data lines and applying at least V<Sub>WDL</Sub> + V<Sub>T</Sub> to all the write select lines of the array.