uc300eth - Overheating processor chip

[Fretty]

Good day to all.
A friend of mine bought a UC300eth controller in late 2017 to use on his CNC. For a while now He has some serious problems.

What can cause the UC300 processor chip to overheat excessively after 80 minuets, to go much longer he has to stop the machine after 60min let the system cool for 30mins before continuing, if he continues, the machine goes erratic, when it suppose to go left it goes right to go up it goes down into the waste board with a vengeance, all required voltages are correct.

Please Note: Within the first hour it's very very smooth sailing with no problems.

Any knowledgeable suggestion is welcome.

Thank you all...

Fretty.

[cncdrive]

I can think of:

- too high ambient temperature.
- ESD damage of the IC.

Or it is not too hot, you just think it is too hot, because please note that it is normal for these ICs to run upto 125°C, they are rated to that high temperature.
Note, that touching a 50°C material is very hot to human hands while it is not hot at all for an IC like this.

Did you measure the temperature of the IC? Or how did you determinate that it is an overheating problem of the IC?

[Fretty]

Dear Sir,
I'm certain it's an overheating problem, a small heat-sink has been attached to the IC a couple months ago which carried the working period to an extra 20mins before the problem starts (please note the room is fully air-conditioned).
Only port 2 is being used with the printer port connection... I'm truly lost.

Any additional advice out there?

Fretty.

[Robertspark]

what breakout board are you using?

How do you have it wired up?

[cncdrive]

I don't have much ideas, have never had any issues like that before and it is fully illogical that the IC overheats, the only possibility I see is that the IC somehow ESD damaged from electric overstress, e.g. human body touch overvoltage.

[cncdrive]

I would check one thing though. I would switch the controller on without anything connected to it nor running, then leave it to the time amount you said that is a problem.
And then connect everything and power up the control box etc. and try to run it.

If then there is still no issue then the problem is somewhere else or if the problem is there instantly then the problem is really with the UC300ETH.

For me it is hard to beleive that it developed this type of problem, but again, it could be somekind of strange ESD damage of the IC, but have never seen anything like this before, so it is just theory, because there is no other logical reason for this kind of problem.

[Fretty]

Dear all,
I was out for a day tying up some loose ends.

I did drop in by my friend to get some info on the Break out Board.
It's a DB25-1205 type, its those type which carries a DB25 Printer socket and uses a DB25 LPT to 26pin IDC flat cable which plugs into
port #2 of the UC300 unit.
This IDC plug and the power supply are all the connections to the uc300 controller.

I'll arrange for him to try and overnight run without the BoB plugged in when he gets back, he will be out for the weekend so I'll get back to you during the up comming week.

Have a great weekend you all.

Fretty.

[Robertspark]

That Bob can prove problematic

https://www.google.com/url?q=http://www ... _jNEBaByGK

https://www.google.com/url?sa=t&source= ... XvrdzFPaNE

I suspect that you have left the jumpers in place and need to remove them as you are probably back feeding 5volts or the ground back into the uc300

[Robertspark]

https://www.google.com/url?sa=t&source= ... VONhhevL2P

[Fretty]

Thanks Rob,
I've documented the info, I'll pass it onto my friend and get back to you with the resualts.

Cheers.

Fretty.