HDD GURU FORUMS

So i recently stumbled across a huge amount of SSDs in my country that uses Chinese controllers. Realtek, Raymax, Innostor, Yeestor, Asolid, Maxwell. And im trying my best to recover those SSDs.

In this line of work i've got many many cases that the problem is with the NAND chip, its gone bad that the SSD can no longer ID those NAND correctly.
However, when reading in PC3000 Flash and Flash Extractor. On a certain power, VCC, VCCq the NAND is IDable and fully readable (of course when reaching certain bad points reading directly PC3k hangs) The SSD uses mainly TSOP 48, BGA 132,152 NAND Chips

So here is my idea, silly question:
I have asked around and found out that, PC3k and FE, VNR can read those chips however there is still no way that we can write the dumps back into those chips
So why is that??
Maybe we should make a device that can write back those dumps into the NAND chips. That will definitely help with the recovery

Maybe i am wrong and still lack of knowledge
If so can anyone tell me where i thought wrong?? Maybe the NANDs are not writable for a reason?

Who said you have to use the vcc / vccq supplied by the pmic / ICs on ssd ?

"half sise" / "full sise"

:-))

It's almost impossible since ECC is calculated based on DATA. Unless you can manufacture a chip that is completely error-free, with an identical geometric structure, and uses the same protocol. In theory, this could be done using FPGA, but the difficulty surpasses your imagination.

Lardman wrote:Who said you have to use the vcc / vccq supplied by the pmic / ICs on ssd ?

Yeah i got what you are saying, to wire vcc vccq from other source. But i don't know how?? Have you done ít? Can you shed some light?

There is several problems to have success:

1. dump quality problem
2. ECC correction. All modern SSD use LDPC
3. config problem. New chips have complicated configs, skips, mask, planes. It will be hard write back in correct way.
4. New chips are very sensitive to temperature
5. Other issues.

gameboybin wrote:Yeah i got what you are saying, to wire vcc vccq from other source. But i don't know how?? Have you done ít? Can you shed some light?

All drives are different, but in general just break the power rail post generation and any feedback if you can and then feed in the voltage you want from your bench supply. Some drives get ancy about powerup order but a few reboots usually shuts them up. Nothing complicated needed.

In-circuit recovery of SSDs with "weak" NAND:
https://www.hddoracle.com/viewtopic.php?f=106&t=2740

fzabkar wrote:In-circuit recovery of SSDs with "weak" NAND:
https://www.hddoracle.com/viewtopic.php?f=106&t=2740

U this is a nice post. Might try it out. Thanks fzabkar!

Lardman wrote:

gameboybin wrote:Yeah i got what you are saying, to wire vcc vccq from other source. But i don't know how?? Have you done ít? Can you shed some light?

All drives are different, but in general just break the power rail post generation and any feedback if you can and then feed in the voltage you want from your bench supply. Some drives get ancy about powerup order but a few reboots usually shuts them up. Nothing complicated needed.

Can you help me out check this upper case??

Here is the underside with the chip taken off

gameboybin, gameboybin,

A very nice, Informative article.