Flash Memory

Today Flash memory is everywhere in Pen drives, Digital camera, MP3 players and in almost all portable electronic devices. Flash memory is a Non volatile Erasable memory device that can be reprogrammed. Dr.Fujio Masuoka of Toshiba introduced the Flash memory in 1984 to the world.

Continue in this link http://www.engineersgarage.com/contribution/what-is-flash-memory

3 responses to “Flash Memory

  1. Flash memory works by modulating charge ( electrons ) stored within the gate of a MOS transistor . The gate is constructed with a special “stack” designed to trap charges (either on a floating gate or in insulator “traps” ). The presence of charge within the gate shifts the transistor’s threshold voltage , higher or lower, corresponding to a 1 to 0, for instance. Changing the bit’s state requires removing the accumulated charge, which demands a relatively large voltage to “suck” the electrons off the floating gate. This burst of voltage is provided by a charge pump , which takes some time to build up power. General write times for common Flash devices are on the order of 0.1ms (for a block of data), about 10,000 times the typical 10 ns read time, for SRAM for example (for a byte).