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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?

Have you checked this yet?

Sharp eyes! I missed that one completely. Will dig down and see what's up.

These two are now repaired but the behaviour is the same; increasing amperage goes up to 15mA but phone does not start.

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

Nokia 3120
https://files.hddguru.com/download/Data ... 4_v2.0.pdf

This one needs might need attention as well. Top left.

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.

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.

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:

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