Memory chip (DRAM)

DRAM, short for dynamic random-access memory, is the working memory of the TV. The system-on-chip uses it to hold whatever it's working on right now: the operating system, the app you're using and video frames on their way to the screen. It's fast but forgetful: when the power goes off, everything in it is lost.

Its silicon die is a vast grid of memory cells. Each cell is one transistor and one tiny capacitor. A charged capacitor means 1, an empty one means 0, and the transistor is the gate that lets the cell be read or written. The charge leaks away within fractions of a second, so every cell is read and rewritten many times a second. That constant refreshing is why it's called dynamic.

To package it, the die is attached to a package substrate. In a common design, the die sits face-down over a slot in the substrate, and bond wires run through the slot from pads along the middle of the die. Mold compound covers the die, and solder balls are added underneath. It's soldered onto the main board. A smart TV usually has a few gigabytes. Robert Dennard invented the one-transistor DRAM cell at IBM in 1966.