Maxtor Hard drive assistance!

[afboarder9889]

Hello,

I have a Maxtor hard drive that I replaced about two years ago (it quit working) so I replaced it with two new hard drives (one for backup).

The Maxtor is a 40gb, DiamondMax Plus 8, 40GB, ATA/133HD hard drive with a S/N of E1ARE2VE.

It has been sitting in a box until recently now I hope to start it up one last time to get my long lost items (mostly personal photos) off of it.

I guess you could say I'm in "DATA RECOVERY MODE" right now. Here's the symptoms:

The PC would get stuck at the "boot up" and I'd have to hit reset numerous times until finally it would boot up. One time it finally just wouldn't do anything.

I did a quick diagnosis and found that it makes no attempt to spin after connected to power. I don't recall hearing clicking or "buzzing". I also had issues with a power supply fan around this time.

I just purchased a "USB 2.0 to SATA/IDE cable system and power supply hoping to be able to jump the drive. I hook the SATA cable in and the red light inside the SATA module lights up red.

Once I hook up the external power supply the light goes out and the drive does absolutely nothing. I have a replacement circuit board on the way. Do you guys think there is anything else I can check before I replace the board?

I really look forward to any available assistance.

Thanks in advance.

 

[afboarder9889]

fzab,

Sounds good. I will measure the Vcore and Vio's on both boards today. again thanks so much for your help.

 

[afboarder9889]

Fzab, Negative results with the recover my files. I am now beginning to check and compare voltages from the new PCB to the old one.

I've discovered a few things:

Q303 PCB 2:

4.5
4.05 3.39


Q303 PCB 1 (Broken Board):

5.3
6.66 1.4

Q302 PCB2:

5.2 3.39 4.5
3.39

Q302 PCB1:

|(5.30) (1.29) (5.3)|

| (1.296) |



SDRAM Voltage:

VDD1: 3.38 VDD2: 3.38

8 pin flash memory: 8th pin showing 3.39 volts on PCB 2.


F7207 MOSFET voltage PCB 2:

MOSFET PCB2:

1.69 0.01 1.69 1.69
3.39 3.39 3.39 2.58


F7207 MOSFET PCB1:
F7207 MOSFIT voltage:

| (.001)(.001)(.001)(.001)
>
| (1.29) (1.29) (1.29) (1.28)




Q303 Bottom left pin on old board with broken chip (according to earlier post) has a voltage of 6.66v. The new PCB is showing a voltage of 4.05 volts.... Interesting to me the old board has more voltage at that lower left pin.

 

[afboarder9889]

fzab,

Look at the supply to the Q302 chip. The PCB 2 (Working board) has a supply of 3.39 volts while the PCB1 (Broken Board) has a supply of only 1.29 volts. It appears as if there is a problem with the supply to this chip...

Also, Look at the supplies for the 8 pin flash memory. Also showing 1.3 volts; are the supplies for the 8 pin flash memory and the Q302 the same? On PCB 1 (broken) both are showing 1.3 while on PCB2 it is 3.39...

 

[fzabkar]

As you say, transistor Q303 is definitely faulty. If this fault were due to physical impact, then the solution would be to replace it. Otherwise, if this is an electronic failure, then it would be unusual for Q303 to fail on its own. That's why I have asked you to measure the voltages and resistances in that area of the circuit.

As you can see from this diagram ...

http://www.users.on.net/~fzabkar/HDD/DiamondMaxPlus8.txt

... the Vio voltage (+3.39V) is down-regulated to produce the Vcore voltage (+1.69V) for the MCU. On PCB #1 you are seeing a Vcore of 0V. I need you to measure the resistance between Vcore and ground. This will tell us whether there is an excessive load on this supply, which in turn may explain why the IRF7207 MOSFET is switched off. If Vcore is shorted, then this may also be the root cause for the failure of the preceding Vio supply.

I would also test the resistances of Q302 on the diode test range, as previously suggested. This will confirm whether a failure in Q302 has caused the Vio load current to be transferred to Q303, which would then explain the failure of Q303.

You are correct in saying that Q302 supplies both the SDRAM and serial flash. That's the Vio rail.

As for why "the old board has more voltage at that lower left pin", this is because the motor controller controls the Vio and Vcore regulators. It does this by sensing the Vio output voltage and then driving the base pin of Q303 to maintain a constant voltage as the load varies. In the case of PCB#1, the motor controller senses that Vio is too low and tries to drive Q303 harder in order to increase the Vio voltage. However, since Q303 is faulty, then the motor controller's control voltage hits its upper limit.

 

[afboarder9889]

OK,

I am not particularly familiar with using diode test ranges. I have my multimeter set to the ->| symbol and these are my readings:

Black test probe on one of the screws holding the board to the drive (ground) and testing MOSFET F7207 Pins 5,6,7,8:

Each of these pins are showing .226 volts on PCB1 (bad board). The PCB2 (new board) has .655 volts on each pin.

 

[afboarder9889]

Q 302 (Diode Test range, grounding on screw terminal)
PCB1, Bad board
|.271 .576 .326

|_____.576


PCB 2, good board
|.267 .595 .322

|_____.595

 

[afboarder9889]

For resistance, my multimeter has only one "OHM" setting. By pressing "Range", I can change my multimeter from "K ohms" (.OL) to "K ohms" (O.L) to "K ohms" (OL.) to "M ohms" (.OL) to "M ohms" (O.L) to "OHMS" (OL.)

I'm not sure which one to set to. If I set it to the "ohm symbol omega" The open loop shows when I touch any drain on Mosfet and on Q 302. I get other results with different settings. This is a DL177 multimeter.

Which setting do I need for measuring these values?

 

[fzabkar]

To test Q302, you need to perform a diode test between its own terminals. Connect your black probe to the Base pin, and then test each of the Collector and Emitter pins with the red probe.

The pinout is as follows:

Emitter - Collector - Base
_________Tab

The metal tab is connected to the middle pin:
http://www.ictradenet.com/models_pic/296-SOT-89-3.jpg

 

[afboarder9889]

Ok. tested like that the values are:


.593 .001 .640

 

[afboarder9889]

On pcb2 the values are

.581. .001. .629

 

[fzabkar]

I believe you have interchanged the collector and base pins, otherwise Q302 is testing OK. I don't know why the Vcore load resistances are testing differently on your two PCBs, but at least there is no short circuit on this supply. Therefore I think it is safe to go ahead and replace Q303.

To this end, either use the transistor from your donor, if you can desolder it without damaging it, or determine the part number of the original component by comparing its dimensions against the following datasheet:
http://www.s-manuals.com/smd-files/pdf/2/2sc1740s,_2sc2412k,_2sc4081,_2sc4617,_2sc5658_r.pdf

If you can't locate the original component, then post back and we'll try to find a suitable substitute.