Help identify transistor from E173FPc?

[Mohonri]

For once, I have a monitor with *good* 2SC5707's. This time, the bad transistor is the MOSFET on the primary side. I've been trying to identify it, so as to find a suitable replacement, but my google-fu is failing me. The markings on it are as follows:
ST logo
WDZ247 (the D could be an O or a 0, the Z could be a 2)
China (this one's not particularly helpful)
PBNK802 (lot/batch/date information)
FP

I can't seem to find any information on it, no matter what combination of (D|o|0)(2|z) I use. Can anyone help me ID this transistor?

If nobody can ID it, then I need to find a suitable substitute. I figure anything with a Vds(max) greater than 250 or so with a current of several amps, with high switching speed, in a TO-220 package (or similar), with the same pin arrangement, should work, right?

[Toasty]

Re: Help identify transistor from E173FPc?

ST P8NK80Z

Wrong line. They'll get you like that.



Below the block, click on "Locate Datasheet" link. Open it in browser, then "File - Save As" in Adobe.

Toast

[Mohonri]

Re: Help identify transistor from E173FPc?

Wow. Right on the money. And how the heck did you know that?

Thanks a ton.

By the way, why is the voltage rating so high? Does the the voltage really spike that high when the transistor turns off?

[Toasty]

Re: Help identify transistor from E173FPc?

Check that mains cap before you put a new FET in there. The fuse went also?

>>By the way, why is the voltage rating so high?<<
Protection; surges; spikes; better ratings; was cheaper than the 600v.....

Picture of board plz.

[Mohonri]

Re: Help identify transistor from E173FPc?

Yup, there's a 2A 250V fuse that went as well, I surmise because the transistor failed. Of course, I don't have confirmation yet that nothing else failed--I received the monitor in less-than-perfect condition. The PWM chip was half-desoldered, and it appears someone tried to replace a cap on the secondary...

...which, on second inspection, has been installed backwards. Eesh, maybe it's a good thing the transistor failed. That could have been entertaining had I fixed everything up and fired it up...

I've attached a picture of the board, with a few annotations. I'm responsible for the removal of the fuse and transistor and for the PWM IC's re-insertion, but the rest is as I received it.

I did a rough test on the big cap, and it appears to be fine.

[Toasty]

Re: Help identify transistor from E173FPc?

Ugh. Hate working on stuff that somebody else has messed with. Always a PITA. You don't know if all the parts are there and, as you found, backwards or half installed.

Before you get too deep into this, you might want to consider buying a new inverter board. IIRC, they run about $40 or so.

Toast

[Mohonri]

Re: Help identify transistor from E173FPc?

While I wait for replacement parts, does anyone happen to know what voltage is on the secondary? On other Dell E17xxxx models, it's typically 12V, but I don't know whether that's the case with this particular model. I'd like to hook up 12V from another source to see whether the inverters work on their own, without the primary.