HDD GURU FORUMS

Have some 480gb SM843TN drives that are security locked. With the success on another post on this forum with unlocking PM863a and PM883, I was hoping there might be a way to force this drive into the ERRORMOD state and use hdparm to secure erase. The drives are showing that the master password is enabled, the drives are locked, security level is maximum.

Here's a link to PCB photos and internal specs, hoping this helps.
https://www.tweaktown.com/reviews/6683/ ... index.html

You could short the I2C clock (SCL) and data (SDA) pins of the temperature sensor IC (2B0 + ACW). Just follow the pinout in that other thread.

Unfortunately, I am not having any luck shorting the SCL and SDA pins and getting the drive to enter ERRORMOD. The drive does not seem to react at all to having those pins shorted to ground or shorted together. I have had a success on the PM863a drives using the method of shorting the MP5505 to ground, wondering if there is something similar on this PCB that would do the same thing.

Did you short the pins before powering up? I don't think any of the other ICs have an I2C bus.

There is a lot happening on this PCB which I don't understand. For example, there appear to be two FN37AP e-fuses (Silergy SY6875A ?). One could be configured as a 5V e-fuse while the second could be a 12V e-fuse. However, the label on the drive makes no mention of 12V.

These e-fuses are located adjacent to the LM10515SQ PMIC.

If 12V is present, then the second GUILL chip (= TPS62130A) at the bottom right corner on the component side would be involved in power loss data protection. To this end I would measure the voltage across the array of 100uF 16V conductive polymer capacitors on the underside. That said, the Enable pin of this IC is connected directly to its positive supply rather than via a pullup resistor, so we cannot short it to ground. Instead, there is a PG (Power Good, pin #4) with a pullup resistor. You could try shorting this pin to ground.

TPS62130A, Texas Instruments, 3V - 17V, 3A Step-Down Converter, marking GUILL, VQFN-16:
https://www.ti.com/lit/ds/symlink/tps62130.pdf

Conductive Polymer Tantalum Solid Capacitors, TDC series, Panasonic:
https://api.pim.na.industrial.panasonic.com/file_stream/main/fileversion/8553

There is a row of 7 JTAG (?) pads at the edge of the PCB. Perhaps one of these is a safe mode shorting point.

Alternatively, you could just use a USB adapter (5V only) and see how the drive is detected without its 12V supply.