ON-CHIP HIGH VOLTAGE POWER FEEDER

摘要

The invention is an improved on chip low voltage to high voltage converter. A capacitive charge pump circuit driven by an asynchronous inverter is used. The charge pump has improved voltage regulation that automatically compensates for process variation in the required program/erase voltage and for charge trapping in the oxide layer of electrically alterable memory products. A charge trapping material that tracks the charge trapping occurring in memory products is used in a feedback circuit to control the output voltage supply. As charge trapping occurs, the output supply voltage is boosted. This overcomes the effects of charge trapping and provides increased cycles of writing and erasing for a semiconductor memory that suffers from charge trapping in its oxide insulation. A dual electron injector structure is used to monitor the charge trapping effect. A typical one order magnitude increase in the number of write or erase cycles before memory degredation occurs can be achieved with this invention.