Rohansi was basically asking 'why', you keep on reiterating that DDR uses more power than LPDDR, but fail to answer why this is the case. Is it clock speed? Is it voltage? Is it a protocol/specification difference? 'various reasons' is not an answer.
replyThere is no physics based reason why it couldn't work. If the industry really wanted to do it they could. But they don't. The primary reason is LPDDR just has too many pins. A DDR5 SODIMM has 262 pins and is an unwieldy beast. LPDDR5 has 644 pins.
replyLPCAMM2 really shows the trade-offs. It adds a lot of bulk and cost, and repairability hasn't been valued high enough by the market to cover that overhead for most consumers. That's why Micron exited the market they played a big part in founding.
https://www.ifixit.com/News/95078/lpcamm2-memory-is-finally-...
LPDDR is very different from DDR so I don't really feel like diving into it in this tiny box. It has its own oscillators so the CPU doesn't have to clock it while asleep; it adaptively refreshes less often according to temperature; during self-refresh the cells are charged to a lower voltage that wouldn't really work for high-speed I/O but works fine for retention.
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