What Is NAND Flash Memory and How Does It Work?

TL;DR

NAND flash memory is an electronic non-volatile memory that can be electronically erased and reprogrammed, consisting of cells with floating gate MOSFETs. It allows for efficient block or page erasing and rewriting of data, making it widely used in storage devices like USB drives and SSDs.

Transcript

hello students in this video we are going to learn about nand based flash memory in our previous video we learned about dram its operation added with their layouts so far we have competed about sram and dram now we are going to learn about a new topic which is flash memory what is a flash memory we know memory is a storage device now what is a flas... Read More

Key Insights

• 👻 Flash memory is an electronic non-volatile memory that allows for electronic erasing and reprogramming.
• 📸 NAND based flash memory uses floating gate MOSFETs in individual flash memory cells.
• ⚡ Read operation in flash memory involves applying a voltage between threshold voltages to determine stored data.
• ⚡ Programming in flash memory involves applying a high voltage to the gate to add electrons to the floating gate.
• 📸 Fowler-Nordheim tunneling is the process used to move electrons in flash memory.
• 👻 Flash memory allows for block or page erasing and rewriting.
• 📸 Flash memory is commonly used in storage devices such as USB drives and SSDs.

Questions & Answers

Q: What is flash memory?

Flash memory is a type of electronic non-volatile memory that can be electronically erased and reprogrammed, belonging to the EEPROM category.

Q: What are the two main types of flash memory?

The two main types of flash memory are NAND based flash memory and NOR based flash memory.

Q: How does NAND based flash memory work?

NAND based flash memory consists of individual flash memory cells containing floating gate MOSFETs, which allow for block or page erasing and rewriting.

Q: How does read operation work in flash memory?

In a read operation, a voltage between the threshold voltages vt1 and vt2 is applied to determine if the cell is conducting (logical 1) or not conducting (logical 0).

Q: How does programming work in flash memory?

To program a flash memory cell, a high voltage is applied to the gate, the drain is connected, and the source is kept floating. This results in a large amount of electrons being stored in the floating gate.

Q: What is the process of moving electrons in flash memory called?

The process of moving electrons in flash memory is called Fowler-Nordheim tunneling, which is a reversible process that allows for adding or removing electrons from the floating gate.

Summary & Key Takeaways

• Flash memory is a type of electronic non-volatile memory that can be erased and reprogrammed, belonging to the EEPROM category.

• There are two main types of flash memory: NAND based flash memory and NOR based flash memory.

• NAND based flash memory consists of individual flash memory cells containing floating gate MOSFETs, allowing for block or page erasing and rewriting.