CompactFlash, SD, MMC, USB flash storage. Anything that does not have moving parts inside.
February 3rd, 2025, 6:33
So this phone landed on our desk. Phone is more or less dead - some activity when trying to power on, but never starts up - and we fail to repair it. A shorted MLCC was found using FLIR and it was replaced so the short was gone. Hooking up the phone to the lab supply it consumes 1mA, and when pressing power button it goes up to 15mA but never turns on.
Looking for the NAND but find no common denominator on the chips so I'm unsure if this is a special one. The largest one caught our attention, it's marked SPANSION 72NS512 (datasheet:
https://www.farnell.com/datasheets/1814146.pdf) but looks more like a controller of some sort.
Attaching photos. Can anyone find a NAND-chip?
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February 3rd, 2025, 7:34
Have you checked this yet?
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February 3rd, 2025, 7:44
Sharp eyes! I missed that one completely. Will dig down and see what's up.
February 3rd, 2025, 9:03
These two are now repaired but the behaviour is the same; increasing amperage goes up to 15mA but phone does not start.
February 3rd, 2025, 9:40
It's not the same PN, but it was the closest I found
look for 72NS512 alldatasheet
https://files.hddguru.com/download/Data ... 274283.pdf
February 3rd, 2025, 10:11
February 3rd, 2025, 13:32
February 3rd, 2025, 14:11
This one needs might need attention as well. Top left.
February 3rd, 2025, 14:50
bos wrote:Phone is more or less dead - some activity when trying to power on, but never starts up - and we fail to repair it. A shorted MLCC was found using FLIR and it was replaced so the short was gone. Hooking up the phone to the lab supply it consumes 1mA, and when pressing power button it goes up to 15mA but never turns on.
Did you measure the voltage at the MLCC afterwards? If it is still 0V, then the DC-DC converter may have failed.
February 4th, 2025, 3:21
it also seems like some components are missing, see pic, bottom right.
Some phones have MCU, RAM and flash stacked on top of eachother, pretty challenging to work with.
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- Capture.PNG (179.61 KiB) Viewed 21882 times
February 5th, 2025, 17:37
bos wrote:Attaching photos. Can anyone find a NAND-chip?
Can't find NAND but found NOR

That BGA 72NS512 is a NOR+RAM multi-chip package, 16-bit databus, 17-bit address bus, here's its block diagram:
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March 31st, 2025, 0:43
The FlashcatUSB XPORT or Mach1 may be able to read the NOR portion with correct wiring, and maybe level shifters if the chip is 1.8v
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