Electronics → Re: What exactly is an "AK33248B8"?

Here's the pictures.

I still haven't had any luck in my searches. I guess the next step would be to try and probe voltages, assuming the part is still in spec.

What brand and model of monitor is this?

It's a Mag Innovision LT765b.

That's a well cooked PCB.

Anyhow, you should be able to determine input/output, GND, and voltages, and put in a TO-220 or so part with equivalent specs.

And at the same time, you may want to look into if something is drawing too much current.

Actually, the PCB itself isn't really damaged at all, it's the sheet of insulating plastic that got, well, not scorched exactly, but really hot and discolored and warped.

I managed to trace and probe what this thing does. It's a 5v to 3.3v regulator that supplies power to an MX10E8050 cpu and a MASCOT VPRL LCD driver chip. Those are the only things drawing power from it. I figure that the problem is one of either the cpu is sinking too much power out of one of its I/O ports, the VPRL is doing the same, or the input voltage is actually too high indicating the upstream 12v to 5v regulator has a problem.

My guess is that the regulator was designed to run with a paper thin margin of its maximum ratings, and an aging component got enough out of spec to push it over. This is one of those annoying situations that only pops up under just the right conditions. I ran the monitor for a half hour out of its case and nothing happened. I guess that being packed into such a tight space when assembled causes excessive heat buildup.

Looks like I'll just have to stick in a beefier regulator, one that I can bolt a heatsink to.

That looks to be a dual package footprint... If you figure out what the part is, might want to bump it up to the larger package.

Look carefully at any decoupling caps. That also looks like it's going to be a multilayer board so it could be taking off in a direction you are not aware of. Troubleshooting this sort of problem is when I really like to have an IR camera, you can actually see slightly warm traces and know where the current is going. I found many a trouble that way.