The flash memory read path: building blocks and critical aspects

The ever-increasing demand for portable equipment is leading to the use of flash memory devices for nonvolatile storage. Fast access time and low power consumption are obviously key requirements. Moreover, multilevel storage techniques are mandatory to reduce the cost per megabit. As a consequence, the READ operation becomes more and more critical, and optimized solutions are needed for almost all circuits involved in the read path. This paper examines the whole read path from addresses to data output, and describes several schemes developed to achieve the required high performances.