Storage chip (flash)

A flash memory chip is the TV's storage, its equivalent of a hard drive. It holds the operating system, the apps you install and your settings, and unlike DRAM, it keeps them when the TV is unplugged.

Each silicon die is packed with memory cells, each a transistor with an extra layer that can trap electrons. A high voltage pushes electrons into that layer, where they stay for years and change how the transistor switches; reading checks for that change. Modern NAND flash stacks its cells vertically, often more than a hundred layers deep, and stores several bits per cell by setting how many electrons are trapped.

TVs usually use eMMC, a package holding one or more flash dies plus a small controller die that manages wear and errors. The dies are stacked on a package substrate, each offset like a staircase so its edge pads are exposed. Bond wires connect each step to the substrate. Mold compound seals the stack, and solder balls go underneath for mounting on the main board.

Flash was invented by Fujio Masuoka at Toshiba in the early 1980s. The name comes from the way a whole block of cells is erased at once, in a flash.