USB-powered Zip Drive does not power on --which part to replace? - Page 1
Forum section: electronics / repair

author: IO Sam
author_rank: Contributor
timestamp: September 09, 2022, 11:15:36 pm
content: I got a new-old-stock USB-powered Zip Drive (100MB) in a sealed box, but when I plug it in (tried multiple cables and PCs) nothing happens... no lights, no noises, no signs of life.I took it apart and (as you can see in the picture) there is nothing looking out of the ordinary. If one of you had to guess which part I should try to replace (caps? electric motor?) to try to bring this unit to life, what would it be?

author: MikeK
author_rank: Super Contributor
timestamp: September 10, 2022, 12:31:28 am
content: Does the Device Manager, or whatever your OS calls it, show anything? I would observe that while plugging in the device.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 12:45:54 am
content: No... Absolutely no signs of life within Windows. I know that 99% of time when these drives break, it is usually a mechanical issue, which means the logic part is usually still functioning. But this drive has been in a sealed box since 2001 and has never been used (opened the box for the first time today), so I think the issue here is something on the electrical or on the logic side that degraded and won't even power up.

author: bdunham7
author_rank: Super Contributor
timestamp: September 10, 2022, 01:09:46 am
content: Put it in a refrigerator overnight and try it in the morning.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 01:13:48 am
content: For real?!?Is that supposed to somehow kickstart some solid state component?And won't the humidity/condensation risk any damage to the other parts?

author: coromonadalix
author_rank: Super Contributor
timestamp: September 10, 2022, 01:20:16 am
content: its not an hdd the freeze method wont work lollhave you tried to connect it thru an powered usb hub, some devices can consume lot of current and some usb ports can't drive them

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 01:22:15 am
content: Yes... I tried both methods (directly to the PC's USB port and through a powered USB hub) to no avail.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: September 10, 2022, 02:31:42 am
content: The freeze technique occasionally works for elx problems. Presumably a fractured solder joint or wire bond is shifted enough to restore continuity. Heat can also work. But success is uncommon and temporary.The easiest answer may lie in your post. Since many failures of these drives are mechanical, find one and substitute the whole board.If you want to do a logical troubleshoot start with a detail visual inspection looking for loose connectors, bad solder joints and signs of flux contamination. Then follow power from the USB input. If these steps don't reveal the problem I would probably just pitch it and find another unit.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 02:55:47 am
content: Thank you! Solid advice! I'm already in the process of procuring a used unit that has only mechanical failure (but still powers up) to replace the logic board. In the meantime, I guess it doesn't hurt to put the unit in a ziploc bag and leave it in the freezer for one night and then see what happens.At any rate, I'll also follow your other suggestion (to follow the traces on the PCB) to see if I can find any signs of continuity problems. This board doesn't have too many through-hole solder joints, which makes it a bit more challenging (for someone not too experienced on these matters like me), but I'll give it a try with my USB digital microscope.

author: Haenk
author_rank: Super Contributor
timestamp: September 10, 2022, 06:41:22 am
content: I assume the two large electrolytic caps are gone.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 06:48:20 am
content: That was my first assumption as well, but wouldn't we see some bulging or some other physical sign of failure for these caps in that case?At any rate, while I understand what the 1000 and 1500 numbers mean on those caps, I'm not too sure about the "6E" and the other 3 digits number on top. Any suggestions that could help me locate the exact replacements for these?

author: alm
author_rank: Super Contributor
timestamp: September 10, 2022, 06:53:20 am
content: I'd search for 1000 uF/ 1500 uF electrolytic caps with a voltage rating of at least 6V in the same form factor.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 07:10:48 am
content: Awesome! Thank you!! I know these are surface-mounted and not through-hole, which means I'll probably need a hot-air station instead of my Hakko soldering iron... A good excuse to finally get one now!Also, when you say "at least 6V", should I try to find out the exact voltage used in this board? Or a ballpark number above 6V would be fine?

author: geggi1
author_rank: Frequent Contributor
timestamp: September 10, 2022, 09:39:31 am
content: Do first check that you get voltages into the PCB. Start at the USB and work your way back.Check the voltages on the processor most likely it is a 3,3V. First have a look at the datasheet of the processors.If you are lucky there is a cracked trace or a bad solder-joint.EDIT!The power-supply stuff is most likely at the end of the USB near the 22uF 10V capacitor.Measure the voltage over the unpopulated pads beside the capacitor.

author: rsjsouza
author_rank: Super Contributor
timestamp: September 10, 2022, 09:43:49 am
content: I think it might be a bit premature to start replacing the capacitors straightaway or suspecting of a board crack. As suggested before, I would connect the unit to a port and see if I can read 5V somewhere on the board - it could be a solder joint on the connector or perhaps even a protection fuse that could have gone with the surge caused by the capacitors needing reforming after all these years.You could also try to use an external current limited bench power supply to power the device through the USB port and rule out any logic issues between the PC and the device, while at the same time be able to monitor the current.All in all, good luck in your repair.

author: Whales
author_rank: Super Contributor
timestamp: September 10, 2022, 10:50:58 am
content: +1 to the abovePlug in USB. Measure voltages, see if the 5V is getting from the connector into the board. Easy way is to keep the black probe of your multimeter clipped to the metal shell of a connector and then hunt with the red probe, starting from all of the pins on the USB connector.Many USB devices will have a fuse OR a resistor acting as a fuse. These might be blown.I doubt the main caps will have shorted, I've never seen that failure mode (outside of "I exploded the whole board"). If the main caps have shorted then you'll be able to observe little to no voltage on the USB connector (the host USB device will/should limit the current if it's USB compliant).

author: CaptDon
author_rank: Super Contributor
timestamp: September 10, 2022, 04:56:29 pm
content: Are you certain that thing is USB powered and doesn't need a wall wart power adapter? It is likely to consume a huge amount of power and depending on your USB port configuration there may not be enough current to run the ZIP drive. In the days of the Xilinx 'platform cables' the older black version needed only 90ma. and would work on every usb port I ever tried. The later red version needed something like 150ma. and a lot of laptop USB ports couldn't push the current unless specific drivers were installed. Those ZIP drives are power hungry. Also for some unknown reason one day they just go zzzzzzzz-click......zzzzzzzzz-click forever and that is the end of their life cycle.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 06:11:38 pm
content: Yeah... The Zip Drive "platform" went through quite a few iterations until the end. They started with wall warts and eventually migrated to be fully USB powered. This unit was THE last version of the 100MB Zip Drive Iomega ever put out in the early 2000's, and it was fully USB powered (it had been for the last 2 versions). So, it does not even have a barrel plug in the back, as the older versions had.While back in the day (late 90's and early 2000's) I never had USB powered Zip Drives, I can imagine many laptops of the time not supplying enough power for these. But today is a different story (at least in my setup), since I collect these things and I now have at least one other Zip Drive (a 250MB version) that was issued more or less around the same time in the early 2000's, that is also fully USB powered and has been working reliably for years on all machines I have tried it on.So, after testing this "brand new" 100MB version in the same PCs than my other 250MB one has been working on, I have to assume this unit had some solid-state components decaying after more than 20 years sealed in a box with no use.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 06:21:17 pm
content: Quote from: rsjsouza on September 10, 2022, 09:43:49 amGood suggestion! When you say "external current limited bench power", how "limited" that current should be for such a test? I understand that USB 1.1 devices such as this would max out at 100 mA in operation.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 06:28:42 pm
content: Quote from: Whales on September 10, 2022, 10:50:58 amSo, in that case I could plug it in my laptop and then test it (I don't own a bench power supply yet, so if this is the case it would be convenient)?As for the caps, I believe these are already polymer solid ones (this unit was made in 2001). So, as you said, I would also expect them to go out in quite a loud fashion instead of dying quietly of old age, right? [EDIT: after some research, I found out that these can indeed degrade and fail with time without any physical signs of damage]If it was indeed a blown resistor, would I need the schematics of this PCB to be able to identify it (if I wanted to avoid testing them all one by one XD)? Or should I look for a "000" resistor (which I could assume to be the fuse)?

author: rsjsouza
author_rank: Super Contributor
timestamp: September 10, 2022, 09:33:26 pm
content: Quote from: IO Sam on September 10, 2022, 06:21:17 pmWell, I would start with a setpoint of 50 or 100mA @ 5V and see if there is current flowing. If there is current and the voltage is reduced, you know that any fuse protection (if exists) can still be operational and I would start increasing slowly the current limiter up until it reaches 5V or 500mA (whatever gets there first). If there is no current at all, then you start suspecting of a fuse or a cold solder joint and start measuring on the board itself.Even if you have current flowing, keep in mind that some older USB-powered devices required split USB cables since the unit drew more than 500mA - given your previous experience with these drives, I don't think you would have missed that but I had to mention that. BTW, USB1.1 could carry up to 5 unit loads like USB2.0, or 5 × 100mA.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 09:55:37 pm
content: All good points! I do have some old school external 2.5 hard drives that came with these split USB cables, but that is definitely not the case with the USB powered Zip Drives. But it is important to know that USB 1.1 can go up to 5 unit loads.Alright! Time to start searching for a decent (and fairly priced) bench power supply...

author: Audiorepair
author_rank: Frequent Contributor
timestamp: September 10, 2022, 10:57:29 pm
content: Quote from: IO Sam on September 10, 2022, 09:55:37 pmHmm, are you seriously suggesting that USB1.1 can power 5 Zip drives?

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 11:07:08 pm
content: If I understand correctly from what rsjsouza wrote, USB 1.1 could potentially supply as much as 500 mA. But a) I'm not sure that would be constant (and thus not sure how many Zip Drives could be attached to a single USB 1.1 circuit) and b) I suspect a Zip drive could have spikes in power draw here and there, but I doubt it would go as high as 500 mA.But then again, don't quote me on any of that...

author: Audiorepair
author_rank: Frequent Contributor
timestamp: September 10, 2022, 11:13:35 pm
content: Quote from: IO Sam on September 10, 2022, 11:07:08 pmI am going to quote you on that.Clearly you have no clue yet pretend to have one.

author: andy3055
author_rank: Super Contributor
timestamp: September 10, 2022, 11:22:11 pm
content: Do the easy things first. As rsjsouza suggested, find a split USB cable and plug in to two ports and see if it will be recognized. If there is not enough current, it will not even start up.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 11:30:13 pm
content: Quote from: Audiorepair on September 10, 2022, 11:13:35 pmOh, I absolutely have no clue and I have no pretention to have one! And that is precisely why I'm here asking so many questions to people who probably have a clue... If I had a clue, I wouldn't be here asking questions now, would I?If you read the thread, you'll see the person who said USB 1.1 goes up to 500 mA (the same as USB 2.0) was rsjsouza, not me (I didn't even know it could go higher than 1 unit load). So, my statement above was my assumption based on the new information provided by the other commenter and not me pretending to know anything (which was made very clear by me asking you to not quote me on that).But then again, powering 5 Zip Drives from a single USB 1.1 port was never my question/statement here in this topic... It was yours.

author: IO Sam
author_rank: Contributor
timestamp: September 10, 2022, 11:33:10 pm
content: Quote from: andy3055 on September 10, 2022, 11:22:11 pmIt definitely doesn't hurt to try... I already have a split USB cable, but it is USB-A (the drive is USB-B), so I'll try to get an adapter to test this.

author: Monkeh
author_rank: Super Contributor
timestamp: September 11, 2022, 12:16:51 am
content: Quote from: Audiorepair on September 10, 2022, 10:57:29 pmNo, he's parroting the language used prior. USB power is allocated in 'unit loads' of 100mA increments, and negotiated power can be up to 5 unit loads, or 500mA.Quote from: Audiorepair on September 10, 2022, 11:13:35 pmPerhaps you're describing yourself here. Or perhaps you should just remain out of threads you've no intention of usefully participating in.Apologies for the side show.

author: fzabkar
author_rank: Super Contributor
timestamp: September 11, 2022, 01:15:31 am
content: Is there a fuse near the crystal that is being obscured by the USB connector?The ISD200 chip (U4) is a USB-ATA bridge. This is the chip that communicates with the USB host.https://www.rockbox.org/wiki/pub/Main/DataSheets/isd200.pdfI would measure the voltages at the capacitors attached to the IC's VDD18 (core) and VDD33 (IO) pins.There appears to be a serial 8-pin "ROM" at U12, probably a 24Cxx I2C EEPROM. If this EEPROM is present, then the device identifies itself to the USB host using the Vendor ID and Product ID of the OEM, in this case Iomega. However, if the EEPROM is absent, the bridge uses its own internal VID and PID, namely 0x5AB and 0x0030, respectively (page 22 of datasheet).You can test whether the bridge is communicating with the USB host by invalidating the EEPROM while powering up the PCB. You could do this by shorting the EEPROM's data output pin to ground.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 05:07:52 am
content: From what I could see around the USB connector housing (macro pictures below) I could not immediately identify a fuse (or a "000" cap), but then I don't have the required "trained eyes" that many of you guys here do for these things... Do you see anything that looks like a fuse in these images surrounding the USB connector housing?As for your suggestions to measure the voltages at the capacitors attached to the IC's VDD18 and VDD33 I, I'll do that as soon as I get my new bench power supply that will allow me to test this board as suggested by a previous commenter.As for shorting the EEPROM experiment, would I need to de-solder its data output pin from the board as well as bridge it to ground with a wire? Or could I just bridge it as it is? (Thank you!!!)

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 05:45:03 am
content: Alright, after macro-shooting the whole board I managed to find two "000" caps which could be the fuses here (although just one of them, S3-side-USB.jpg, is immediately close to the USB plug housing). I'll test both of these later and report back.

author: fzabkar
author_rank: Super Contributor
timestamp: September 11, 2022, 06:00:55 am
content: It should be OK to short the EEPROM's data pin to ground in-circuit. Data recovery guys do this all the time. I was originally reticent, but they convinced me it was OK. You only need to maintain the short until the PCB powers up, then you can release it. That's because the bridge IC only looks for the EEPROM immediately after power-on and then ignores it.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 06:11:48 am
content: Nice! That sounds a lot easier!If bypassing the EEPROM should work, would that mean it's bad and should have its data pin permanently disconnected/grounded?At any rate, I now have a full check list of things to try... Hopefully I'll find the culprit in one of these steps! Thanks again!!

author: fzabkar
author_rank: Super Contributor
timestamp: September 11, 2022, 06:44:53 am
content: If, after bypassing the EEPROM, the bridge IC appears in Device Manager, this will prove that the bridge IC is not brain dead, and it will verify the USB link. Then you will need to look elsewhere for a culprit.I notice that there is a transistor at Q3 (near the USB connector) which is marked "PT". I'm betting that this is configured as a high side power switch. I'm guessing that it is a P-channel MOSFET with 4 drain pins, 1 source pin and 1 gate. If it is switched on, then the D and S pins should be sitting at +5V.This device is probably equivalent to Q3:http://www.aosmd.com/pdfs/datasheet/ao6405.pdfI can't see what is under the sticker, but I expect that you will find a microcontroller with an ATA interface, a read/write channel IC ("B9"), a serial flash memory (AT27LV520), and a motor controller (U8).

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 07:10:20 am
content: Thanks again for all these tips! I removed the sticker and you can now see the markings on the ICs.

author: Haenk
author_rank: Super Contributor
timestamp: September 11, 2022, 07:10:22 am
content: I still would check the caps first.If I remember correctly, these drives will do a medium check on powerup, i.e. starting the motor. USB power might not be enough for that (there is a reason, these split USB cables exist, USB powering was very close to the edge back then). So that cap might be needed for the spike in current draw.Might be a stuck motor as well.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 07:16:28 am
content: I'm getting a USB-A to USB-B adapter (to use with my existing split USB cable) this Monday. So I'll be able to plug the drive with the extra juice to test this hypothesis. And I am definitely testing all these caps with a multimeter this week as well.As for a possible stuck motor, wouldn't the drive at least light up (and be seen by the OS) if that was the case?

author: Whales
author_rank: Super Contributor
timestamp: September 11, 2022, 07:27:16 am
content: Quote from: IO Sam on September 10, 2022, 06:28:42 pmYes. Your laptop should have polyfuses (or similar active protections) in the USB ports to prevent too much current exiting its ports. Otherwise every faulty USB device would damage your laptop.I don't know why you would bother with a bench power supply here. If the device is drawing a reasonable amount of current then your laptop will supply it fine, if it's trying to draw too much then your laptop will refuse to supply it (eg voltage will drop OR it will get turned off, possible repeatedly cycled on/off/on/off). A bench power supply could let you do the same (with more effort) or it could let you provide more current... but that's not a safe diagnostic methodQuoteAgain I think this is unlikely. There are hundreds of unlikely things I could list, I'm not sure where the focus on electrolytic caps came from.Measure more, guess less.QuoteNo need for schematics. It will be wired very close to the USB port and you can use your multimeter on continuity buzz mode to find it (edit: whilst the unit is unplugged from power! otherwise the multimeter will be confused). It will almost always be the first thing wired to the +5V pin of the port.Yes 00, 000 or similar if it's a resistor. If it's a fuse style package then it might be a different colour or have a letter written on it instead of a number.Stop asking questions and go have a lookPlugging it into USB power and probing with a DMM is unlikely to cause any harm as long as you are careful to (1) keep the multimeter on volts (not amps) mode and (2) don't short nearby pins/pads out.Once you have more information we may be able to help you more. At the moment all we can do is guess. Power supplies are always a good place to start looking.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 04:39:49 pm
content: Thank you for your commentary and tips here! As my collection of vintage hardware grows, I see the need to learn more about how to repair these things myself and that is why I'm considering acquiring some additional gear such as a benchtop power supply, hot air station, oscilloscope, etc. But it is great to know (from your experience) that my existing laptop can be used safely for this particular project.My main concern when repairing old gear is safety, since some of these things are getting harder to find (and more and more expensive). So, one might understand my excessive care and precaution here.As for questions, I asked enough of them already... I have enough here to work with for days now! And, as a newbie in this forum, I have to say I'm blown away by the amount of helpful and useful tips and suggestions I got in this topic! I'm stoked to have found this place and it is pretty incredible to see the nice community that Dave managed to build here!Thanks to everyone who tipped in, and I'll post the results of this little project here as soon as I have some updates.

author: fzabkar
author_rank: Super Contributor
timestamp: September 11, 2022, 05:15:22 pm
content: Those capacitors of that era were prone to leakage, and this would often corrode the PCB tracks. That said, these failures would usually be associated with a fishy smell.Here is the datasheet for the AT27LV520:https://pdf.dzsc.com/V52/AT27LV520.pdfIf there is no Vcc, I would check whether Q3 is being turned on.I suspect that the bridge IC controls power to all the other chips via Q3. If there is no activity on the USB link, I suspect that the bridge turns off Q3, thereby switching the drive into power saving mode. If Q3 is off, then this would point to the bridge as a suspect. But that's all just conjecture.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 05:18:29 pm
content: Quote from: fzabkar on September 11, 2022, 05:15:22 pmI'm glad to report that there were no caps leakage here!

author: tooki
author_rank: Super Contributor
timestamp: September 11, 2022, 05:58:24 pm
content: Quote from: IO Sam on September 11, 2022, 07:16:28 amI wouldn’t. Adapters like that aren't even supposed to exist.Especially given the fact that wealready knowit doesn’t need two ports’ worth of current: it shipped with a standard single-headed cable. See the manual attached.Some weird USB adapter simply runs the risk of frying something. Don’t do it.

author: james_s
author_rank: Super Contributor
timestamp: September 11, 2022, 06:13:49 pm
content: If you're getting 5V to the circuit then my best guess is that the firmware has become corrupted, 20 years is about when eproms and flash, at least older flash, start to suffer problems from bit rot. This is especially true if it was exposed to elevated temperatures.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 06:25:16 pm
content: Quote from: tooki on September 11, 2022, 05:58:24 pmYou are correct that the drive came with a simple (non-split) USB cable in the box. I wonder if the other commenter was suggesting the use of a split cable just for testing purposes (I have no idea if the extra power from a dual lead cable could somehow help to recharge these old capacitors or something of the sort).

author: Monkeh
author_rank: Super Contributor
timestamp: September 11, 2022, 06:27:30 pm
content: Take a look at Y1 from a different angle.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 06:30:15 pm
content: Quote from: james_s on September 11, 2022, 06:13:49 pmAs I test the PCB with my multimeter this coming week, this is something I intend to find out (even bypassing the EEPROM as another commenter suggested). I have Zip Drives in use for decades now without a hitch, but the fact that this one was never used for over 20 years indeed puts this unit in a different set of variables as far as firmware bit rot is concerned.

author: IO Sam
author_rank: Contributor
timestamp: September 11, 2022, 06:58:38 pm
content: Quote from: Monkeh on September 11, 2022, 06:27:30 pmY1 macros galore below:

author: MikeK
author_rank: Super Contributor
timestamp: September 11, 2022, 07:45:03 pm
content: Two pins on the right side of U4 appear to be solder-bridged.[ Specified attachment is not available ]

author: Monkeh
author_rank: Super Contributor
timestamp: September 11, 2022, 07:47:55 pm
content: I saw those, they're fine - one is Vss and one is TEST3 which needs to be tied low. That bridge appears to be in the classic position for a trace linking two pads with no mask. I'd probably try removing it, but I'd also remove the chip to see where those pads are supposed to be going first - probably a bit advanced for this case..