USB flash. What does it consist of. What is NAND memory and controller?

USB flash drives or Micro SD memory cards have long replaced optical storage media, and if an optical disk is visible, what it consists of, then the insides of a flash drive are not visible because of the case. Basically, such removable storage media consist of a memory chip - NAND flash memory and a chip, thanks to which there is an exchange of signals between the computer and the flash memory chip and not only, this chip is called a NAND controller. Micro SD memory cards also consist of these two chips

The NAND microcontroller contains a USB controller, a microprocessor, RAM, a generator and a module for "communication" with a flash memory chip. Thanks to the controller, data is restored in the flash drive, information recording is controlled and other functions are performed.

The NAND flash memory chip, it determines how many Gigabytes the flash drive will have. In the photo, a chip with 8 Gbytes of memory. There can be two such chips in a USB flash drive.

On phone boards, there are also flash memory chips, they, like Micro SD, contain a controller and flash memory and are a ready-made flash drive for several Gigabytes. The name of such chips is EMMC memory