Industrial LCD monitor DSP overheating

[PowerAmpFreak]

Hello
In front of me I have an industrial LCD monitor, brand is General Touch PL1501.
It works for a few minutes then starts to make odd colours and behave bad.
I traced it to the chip "TSU16AK" DSP overheats, if I use freeze-spray on it, the operation will be restored a few minutes until it overheats again.
I might think of replacing the entire pcb, if I just could locate it.
I haven't got a clue where to search for this, since it has got no readable numbers on it.
Replacing the chip only might be a solution, but only locate the chip on E-bay (China).
Any advice is appreciated!

[tom66]

Re: Industrial LCD monitor DSP overheating

Check all nearby voltage regulators for stability.
It is unusual for such a chip to fail in such a way. Not impossible but very unusual.
Freeze spraying it may reduce the current it uses, this may affect regulators nearby.

[budm]

Re: Industrial LCD monitor DSP overheating

'Check all nearby voltage regulators for stability.' +1
Does it get hot if you disconnect the LVDS cabl going to the LCD Panel?

[stj]

Re: Industrial LCD monitor DSP overheating

are you assuming it overheats, or can you burn your finger on it?

if you can put a finger on it then it may just need a reflow.

[fzabkar]

Re: Industrial LCD monitor DSP overheating

The SM89516C25J SyncMOS microcontroller runs off +5V, so I expect this would be provided by a switchmode converter consisting of the toroid (L3), U3 and D1.

The TSU16AK requires a 1.8V core and a 3.3V I/O supply, so I'm guessing these are provided by linear regulators near the crystal.

You might consider attaching a heatsink to the TSU16AK.

SM89516C25J, SyncMOS, 8-bit microcontroller with 64KB flash & 1KB RAM, 5V, 25MHz:
https://cdn.badcaps-static.com/pdfs/...9d89632815.pdf


TSU16AK, MStar, SXGA LCD Controller with Analog Interface and Dual LVDS Transmitter, 1.8V core, 3.3V I/O:
https://cdn.badcaps-static.com/pdfs/...4e8c117680.pdf

[PowerAmpFreak]

Re: Industrial LCD monitor DSP overheating

Thanks everyone for good advice.
I don't burn my finger on it though.
Already tried a heatsink but it does not help much.
I will focus on the voltage regulators.

[fzabkar]

Re: Industrial LCD monitor DSP overheating

Apart from a reflow, could a wonky crystal (X2) produce the observed symptoms?