SSDs use flash memory, a type of memory that retains data even when the power is turned off. The basic unit of storage in NAND flash memory is a . Each memory cell is made up of a transistor and a . To write data to a memory cell, a high voltage is applied to the control gate of the transistor, causing electrons to the oxide layer and onto the floating gate. This process is called , and the presence or absence of electrons on the floating gate determines whether the cell stores a 1 or a 0.
To erase data from a memory cell, a high voltage is applied in the , causing electrons to the floating gate and return to the substrate. During a read operation, the state of a memory cell is determined by measuring its . A small voltage is applied to the control gate, and the resulting current flow through the transistor is measured. Based on this current flow, the controller can determine whether the cell is storing a 0 or a 1. NAND flash memory can store multiple bits of data per cell through techniques such as multi-level cell (MLC) and triple-level cell (TLC), allowing for higher .
SSDs are commonly used in laptops, desktops, servers, and data centers. They come in different , including 2.5-inch SATA drives, M.2 drives, and PCIe-based drives. SSDs offer significantly faster and write speeds compared to HDDs, leading to improved system performance. However, SSDs are typically more per gigabyte of storage compared to HDDs. Flash drives use NAND-based flash memory similar to SSDs and are small, portable storage devices with a USB interface, widely used for , backup, and storage in a portable form.
Keywords
nand-based | data read | form factors | tunnel through | floating gate | programming | reverse direction | data transfer | data density | conductivity | expensive | non-volatile | tunnel off | memory cell |
