tehsiggi wrote on 2025-09-23, 10:51:

Yep, you just ripped of it's dual FET (Q9) :D No more switching there, that's for sure. […]
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Yep, you just ripped of it's dual FET (Q9) 😁 No more switching there, that's for sure.

While it's gone (lol) feel free to measure the resistance between MVDDQ and GND.

Here's btw. a picture of the SS pin from ISL6522 with over-current protection active:

The attachment Screenshot 2025-09-23 at 12.48.38.png is no longer available

Yellow is the waveform of interest. I think blue was one of the Gates, either high or low-side. In this case the FET for the low side had a disconnect on it's gate. Leading to the voltage not being generated correctly.

Well that’s the end of that 🤣. The FET refused to come off the heat sink so got some pliers and slowly twisted side to side, the IC eventually came off but unfortunately one of the legs broke off. The factory glued every chip under 🥲

RIP.

The FET is a STS8DNF3LL or comparable. Dual nFET with 30V rating and 8A. With good RDSon at 4.5V as well.

tehsiggi wrote on Yesterday, 07:06:

RIP.

The FET is a STS8DNF3LL or comparable. Dual nFET with 30V rating and 8A. With good RDSon at 4.5V as well.

https://www.digikey.com.au/en/products/detail … S8DNF3LL/603495 looks alright?

Yep, looks good. Did you get a reading on resistance between MVDDQ and GND?

tehsiggi wrote on Yesterday, 07:31:

Yep, looks good. Did you get a reading on resistance between MVDDQ and GND?

Yep it's 69.8 ohms

Don't want to interrupt you guys, but did you check that ferrite? Looks suspicious on the photo but could also just be some dirt. Also the tantalum(s) below have somewhat black marks.

ChrisK wrote on Yesterday, 08:00:

Don't want to interrupt you guys, but did you check that ferrite? Looks suspicious on the photo but could also just be some dirt. Also the tantalum(s) below have somewhat black marks.

That'd be the input ferrite for MVDDC or VTT, I suspect if it's a goner, we'd have a voltage missing here. (Un-)fortunately, those are there and look fine. The dirt dot looks suspicious, I agree.

zuldan wrote on Yesterday, 07:41:

Yep it's 69.8 ohms

That sounds good so far! Similar to my card, so no hard short at least.

ChrisK wrote on Yesterday, 08:00:

Don't want to interrupt you guys, but did you check that ferrite? Looks suspicious on the photo but could also just be some dirt. Also the tantalum(s) below have somewhat black marks.

Thanks for noticing that. I cleaned with IPA and it appears just to be dirt.

ChrisK wrote on Yesterday, 08:00:

Don't want to interrupt you guys, but did you check that ferrite? Looks suspicious on the photo but could also just be some dirt. Also the tantalum(s) below have somewhat black marks.

The attachment Ferrite.PNG is no longer available

Diode looks dusty or faulty too

Where do you see a diode on that picture?

Brain fart.
Tantrum caps.