I had that problem with one device too. A wireless Microsoft mouse that I used for a laptop. I bought another, and the same thing happened. It was always the base.

Added a 12" USB surge protector http://www.l-com.com/surge-protecto...pe-a-type-a-panel-mount-style-with-pigtail-12 and no issues.

There is a KA2 here: http://www.s-manuals.com/smd/ka which is a switching diode.
If used for protection, it might not work.

Since it cost 500 Euros, will the manufacturer fix it for much less? Would they work with you to solve the problem? e.g. identify the failed part?

I had a issue with a stepper motor controller for an X-ray goniometer. This was RS232 based. With a 100 kV @ 0.1A power supply and a big transformer, the RS232 drivers kept blowing out. The MFR just suggested replacing the chips. They were socketed. I did chose isolation to fix that problem.

Back in the day, I fixed a fair amount of stuff that head reliability issues. A thermocouple scanner quit scanning when used near 1000 W IR lamps. I obtained the schematic and the entire regulator section was missing. I added two Transorbs. It was basically CMOS IC;s that broke with no restraint on the power supply.

I had a surround-sound receiver that came back to the shop twice that I did occaisional work for. the root cause was the Vcc of one of the amplifier IC's was way too close to the absolute maximum voltage. Transorbs fixed that.

We had just purchased a $5000 instrument from a well-known instrumentation company and it was destroying our devices. The company was skeptical, but agreed to investigate. They nearly instantly provided an external adapter for us ti use that crippled the instruments other functions, but it worked. They later modded the instrument for free once a final fix was designed.


On a slow turn-on circuit, I designed for a home-made amplifier, that circuit would fail. There was effectively 50,000 uF of capacitance at 50 V. An opto-isolator, a zener diode and a resistor were connected to the LED portion. The LED would die. Fix was ZNR's across each capacitor.

In a manual sweep generator I designed, it would fail. I had to protect the OP-amp input.

One of the hardest and scariest problems i had was the design of a I-V converter front-end for a lock-in amplifier for an in-house measuring system. It worked on our research grade solar cells, but not the large area ones used for calibration. That required a buffer to isolate the capacitance of the solar cell.

My fixes tended to be better if possible.

Changing capacitors after 5 years is expected. I probably could have fixed that too. It was primarily the negative rail of an OP-amp that had lots of ripple. It was the norm to replace all for a particular model of ION gauge we used and self-repaired.

A bunch of Sorenson power supplies also had the capacitor issue.

An arc-lamp power supply failed. 40 A at 22V with a 40 kV ignite spike. I found the rectifier bridge was only 10A. I worked with the manufacturer and they modded the supply for free. New transformer and new bridge.

Their earlier ignitors failed miserably. I made them better until they made it internal to the lamp housing and did that modification for free also. Replacing the spark gap was a normal maintenance item.

Some manufacturers work with you and others do not.

Apple did not work with me at all with respect to a modem in a recently purchased iBook. They fixed the modem 6 months later with a firmware upgrade. If you mailed a message with ATH$ in the body of an email, the modem will hang up.

We had a $5000 multi-channel analyzer fail 2x with a $1000 board exchange/repair. Since we had schematics, I looked and there was absolutely no surge suppression internally. Manufacturer said, we specify 120 V 60 Hz and a surge exceeds that.

In the case of a measurement system that we were highly dependent on, I used a power conditioner from what was ONEAC, now PowerVAR and an ISOBAR surge suppressor.
The Mac Centris 650 computer and associated measurement system was still operating at 17 years before re-designed and replaced. The SCSI hard drive did not have a failure either. The failures seen were dust, fan dust and floppy drive.

There are parts specifically for USB port protection. See: https://www.st.com/en/protection-devices/usb-port-protection.html?querycriteria=productId=SC1489 as an example.

 

Assuming there's no warranty, I wonder if the manufacturer would give you any help determining why this part may have failed, or at least help you determine what its purpose is, so that maybe you can figure out if its failure is the cause or just a symptom of the real cause. Perhaps the board needs to be in a specific state before it's unplugged? Worst case, swap that part and see if it comes back to life.

The manufacturer has already offered to repair the items against normal tariffs (About 70 eu). However I can use the devices using their CAN port which seem to work fine so I will not be using that service. It's just that I don't like damaging these expensive units and feel like I need to learn for self improvement and better designs from my part in the future. At this time I'm not able to replace the parts because the devices are in machines that will be used very soon.

I had that problem with one device too. A wireless Microsoft mouse that I used for a laptop. I bought another, and the same thing happened. It was always the base.

Added a 12" USB surge protector http://www.l-com.com/surge-protecto...pe-a-type-a-panel-mount-style-with-pigtail-12 and no issues.

There is a KA2 here: http://www.s-manuals.com/smd/ka which is a switching diode.
If used for protection, it might not work.

Since it cost 500 Euros, will the manufacturer fix it for much less? Would they work with you to solve the problem? e.g. identify the failed part?

I had a issue with a stepper motor controller for an X-ray goniometer. This was RS232 based. With a 100 kV @ 0.1A power supply and a big transformer, the RS232 drivers kept blowing out. The MFR just suggested replacing the chips. They were socketed. I did chose isolation to fix that problem.

Back in the day, I fixed a fair amount of stuff that head reliability issues. A thermocouple scanner quit scanning when used near 1000 W IR lamps. I obtained the schematic and the entire regulator section was missing. I added two Transorbs. It was basically CMOS IC;s that broke with no restraint on the power supply.

I had a surround-sound receiver that came back to the shop twice that I did occaisional work for. the root cause was the Vcc of one of the amplifier IC's was way too close to the absolute maximum voltage. Transorbs fixed that.

We had just purchased a $5000 instrument from a well-known instrumentation company and it was destroying our devices. The company was skeptical, but agreed to investigate. They nearly instantly provided an external adapter for us ti use that crippled the instruments other functions, but it worked. They later modded the instrument for free once a final fix was designed.


On a slow turn-on circuit, I designed for a home-made amplifier, that circuit would fail. There was effectively 50,000 uF of capacitance at 50 V. An opto-isolator, a zener diode and a resistor were connected to the LED portion. The LED would die. Fix was ZNR's across each capacitor.

In a manual sweep generator I designed, it would fail. I had to protect the OP-amp input.

One of the hardest and scariest problems i had was the design of a I-V converter front-end for a lock-in amplifier for an in-house measuring system. It worked on our research grade solar cells, but not the large area ones used for calibration. That required a buffer to isolate the capacitance of the solar cell.

My fixes tended to be better if possible.

Changing capacitors after 5 years is expected. I probably could have fixed that too. It was primarily the negative rail of an OP-amp that had lots of ripple. It was the norm to replace all for a particular model of ION gauge we used and self-repaired.

A bunch of Sorenson power supplies also had the capacitor issue.

An arc-lamp power supply failed. 40 A at 22V with a 40 kV ignite spike. I found the rectifier bridge was only 10A. I worked with the manufacturer and they modded the supply for free. New transformer and new bridge.

Their earlier ignitors failed miserably. I made them better until they made it internal to the lamp housing and did that modification for free also. Replacing the spark gap was a normal maintenance item.

Some manufacturers work with you and others do not.

Apple did not work with me at all with respect to a modem in a recently purchased iBook. They fixed the modem 6 months later with a firmware upgrade. If you mailed a message with ATH$ in the body of an email, the modem will hang up.

We had a $5000 multi-channel analyzer fail 2x with a $1000 board exchange/repair. Since we had schematics, I looked and there was absolutely no surge suppression internally. Manufacturer said, we specify 120 V 60 Hz and a surge exceeds that.

In the case of a measurement system that we were highly dependent on, I used a power conditioner from what was ONEAC, now PowerVAR and an ISOBAR surge suppressor.
The Mac Centris 650 computer and associated measurement system was still operating at 17 years before re-designed and replaced. The SCSI hard drive did not have a failure either. The failures seen were dust, fan dust and floppy drive.

There are parts specifically for USB port protection. See: https://www.st.com/en/protection-devices/usb-port-protection.html?querycriteria=productId=SC1489 as an example.

Thank you for your in dept stories. I think your stories show that even big manufacturers make design choices that could potentially be detrimental to other devices and that you can actually do alot to prevent damage to other devices.

 

I did discover a flaw from my part which I think could atleast be a part of why the devices are failing.
The docking station has a power plug with three leads and I have been powering the wrong leads. The + was connected correctly but the - was probably not connected at all. I think the device could provide the - for the docking stations. Which means that all charging current for the tablet would be going through the USB cables and the device.
Maybe this is what is causing the device to break.

 

That may be it. Swap that chip on the board, fix your wiring issue and see what happens!