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Data recovery and disk repair questions and discussions related to old-fashioned SATA, SAS, SCSI, IDE, MFM hard drives - any type of storage device that has moving parts
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Board Repair Quantum Fireball CX 20.4AT

April 2nd, 2021, 13:39

Hi Techs,

I found out the issue with the drive. It has a very burnt IC, it was under a metal guard that protects the ribbon cable.

Was wondering if my board repair guy(he's excellent fixes 5 MacBook logic boards a day), could try replacing the blown chip from the donor or if maybe that 6 legged chip(X17 ZB) was important that's next to it. The chips have different markings, even though the donor board is an exact match.

If I just swap the donor board it has a blinking green light. Is there EEPROM or other memory chip on these that needs to be swapped?

I have a deepspar, but I can also send it to my friend with a PC-3000 to get a better diagnosis, or maybe find a place that can do a hot swap, but from what I've read matching head maps on these is a nightmare.

Appreciate any input you have?
Thanks in advance!

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Re: Board Repair Quantum Fireball CX 20.4AT

April 5th, 2021, 19:07

Move broken part from good board.

Re: Board Repair Quantum Fireball CX 20.4AT

April 5th, 2021, 21:01

I suspect that the blown IC is a pass transistor in a linear regulator. Measure the voltages on the donor IC.

X17 is a dual transistor.

IMX17, Rohm, dual NPN GP transistor, 50V, 500mA, marking X17, SC-74:
https://www.mouser.in/datasheet/2/348/imx17-208895.pdf

BCX52, NXP, PNP transistor, -60V, -1A, marking AE, SOT89:
https://assets.nexperia.com/documents/data-sheet/BCP52_BCX52_BC52PA.pdf

I believe this PCB has a terminal output.

The 8G9V/8G9P component is a 3-terminal linear regulator, probably +8V or +10V.

Re: Board Repair Quantum Fireball CX 20.4AT

April 6th, 2021, 0:51

This drive has terminal. There is no external rom chip.

Re: Board Repair Quantum Fireball CX 20.4AT

April 6th, 2021, 7:20

The good transistor on the donor PCB is a 2SB1073, so perhaps BCX52 was the wrong choice for the blown transistor.

2SB1073, Panasonic, PNP transistor, -20V, -4A, hfe = 120 to 205, marking IQ, miniP3-F1:
https://docs.rs-online.com/e4c1/0900766b80c023ac.pdf

XN04502, Panasonic, dual NPN GP transistor, 50V, 0.5A, marking 5Q, Mini6-G1:
https://docs.rs-online.com/187b/0900766b80c0f46a.pdf

Re: Board Repair Quantum Fireball CX 20.4AT

April 6th, 2021, 14:54

This boards, specially these motor/VCM drivers are specially problematic.
They catch on fire. This are the 3.3 regulator transistor, controlled by the Panasonic or Philips power driver.
Is very propably that the motor driver caused this regulator to catch on fire.
If you substitute the board to the exact one (same serial number, but I already get success changing one that had only diferent REV numbers) you can probably bring it back to life. :D

Re: Board Repair Quantum Fireball CX 20.4AT

April 7th, 2021, 16:22

AN8428GAK, Panasonic, motor combo IC for 3.5inch HDD:
http://www.datasheetcatalog.org/datasheets/166/488890_DS.pdf

The suggested pass transistor is a 2SB1073 and the dual transistor is an XN4502.

I expect you could replace the 3.3V transistors with a 3.3V LDO regulator.
Attachments
AN8428GAK_3V3_reg.gif

Re: Board Repair Quantum Fireball CX 20.4AT

April 9th, 2021, 4:39

According to my memories, these boards can be swapped without other actions. Drive should be working with the new pcb at once.
However, it probably does not spin up without connecting the preamp cable.

pepe
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