Your phone's memory is leaking right now. Phones and PCs use the same kind of RAM (DRAM: LPDDR in phones, DDR in PCs). Zoom into one memory chip and you find a grid of tiny cells: 8 GB of RAM holds about 69 billion of them. Each cell is one transistor (a switch) and one tiny capacitor (a bucket for electrons). A charged capacitor is a 1, an empty one is a 0.
The catch: every capacitor leaks. Left alone, a 1 fades into a 0. So your RAM reads every row and tops it back up, at least every 64 milliseconds (DDR5 does it every 32), even when your phone is doing nothing. That's the "dynamic" in DRAM. Cut the power and the refreshing stops, which is why RAM forgets everything when you shut down.
Episode 1 of "How it works": everyday tech, zoomed all the way in.
Sources:
DRAM cell (1 transistor + 1 capacitor; charge = 1, no charge = 0): https://www.halbleiter.org/en/digital-technology/dram-cell/
DRAM read, write and refresh: https://eesemi.com/drams.htm
Refresh window 64 ms (DDR4) / 32 ms (DDR5): https://arxiv.org/abs/2209.10198
Phone RAM is LPDDR (low-power DRAM), JEDEC LPDDR5: https://www.jedec.org/standards-documents/docs/jesd209-5c
8 GB = 8 × 2^30 × 8 = 68,719,476,736 bits
Should I zoom into the CPU next? Tell me in the comments. Learned something? A like or a share really helps.
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I'm Haris. I make videos about the tech that actually matters.
More of my work: https://bytefy.in
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