A common feature of storage devices today is NAND flash memory, which has become an integral part of modern electronics.
With its increasing popularity and the need for more features, the demand for NAND flash memory will continue to grow because of the increasing data storage needs.
Here’s what you need to know more about NAND technology and how it helps with modern storage.
What is NAND Flash?
The Nand flash is a non-volatile storage medium that requires no external power to function. Its arrays store up to four bits of data defined by transistors.
An individual transistor consists of two gates through which current flows. The control and floating gates regulate the energy flow in flash memory cells.
Uses of the NAND Flash
NAND Flash devices do not consume any power when storing or transferring data, which makes it a faster and more flexible method to move or shift data.
The NAND flash is everywhere, and you may find it in Solid-state drives (SSDs), NVME drives, USB Pen drives, mobile phones, and smart TVs.
The NAND Flash comes in two grades, industrial and consumer, with significant differences. When choosing NAND Flash for your application, you should consider its impact on reliability, longevity, security, and ownership costs.
How NAND Flash Works
The NAND flash stores data in rows of memory cells made from gate transistors, and there are two gates in the circuit, namely the floating gate and the control gate.
And to program one cell, the control gate must receive a voltage charge. This gate then attracts electrons, and the floating gate traps them within the substrate, allowing them to stay inside.
A voltage is needed on the other side of the substrate to erase a cell. Over time, continuous erasing, reading, and writing will wear out the flash memory components. So, a NAND flash is rated based on how many programs or erase cycles it can perform.
Types of NAND Flash
In simple terms, NAND Flash represents data by storing electrical charges within each cell. The more bits stored in each memory cell, the greater the density when multiple layers are stacked vertically, lowering the cost of the NAND flash.
Here are the different types of NAND memory:
1. The single-level cells (SLC)
The SLC Flash stores a single bit of memory on every memory cell. It has two levels, resulting in a high voltage margin between them. The high voltage makes reading the cell easier and faster, with minor wear. The SLC is often used in non-cost-sensitive applications that require high durability and reliability.
2. The Multi-level cells (MLC)
The MLC Flash stores two bits of data on each memory cell against three levels. The read operation must be more precise since there are more levels to compare, which leads to slower reads than SLC Flash.
It also has a more significant impact on wear, which reduces the lifetime P/E cycles. But its lower cost per bit makes it suitable for cost-sensitive applications like gaming.
3. Triple-level cells (TLC)
The TLC Flash stores three bits of data on each memory cell on seven levels. Since there are many levels to compare, read operations are exact and slow, increasing wear and significantly decreasing lifetime P/E.
The TLC has the lowest bit cost, which is suitable for budget-conscious applications such as consumer applications.
4. The 3D NAND
The 3D NAND vertically stacks the flash memory cells to increase storage density. The vertical stacking of NAND cells provides several advantages, including the possibility of spacing transistor cells so that adjacent cells do not interfere. The cell becomes more stable and long-lasting as a result.
Conclusion
The NAND Flash allows your storage to run faster and consumes no power to store or retrieve data. This is why it is available on almost all storage devices, especially pen drives and SSDs.
As new technologies emerge, memory cells may be able to hold a byte of data with more vertical layers.
