Iiyama 2607WS suddenly dead

[formatthias]

Re: Iiyama 2607WS suddenly dead

The measurements are exact. It is not a regulator. It is a MBR20100CT.



I have to go to sleep now, thank you so far for your help.

[budm]

Re: Iiyama 2607WS suddenly dead

I know it is not regulator but I still need the Ohm readings using Ohm scale, not voltage readings.

[formatthias]

Re: Iiyama 2607WS suddenly dead

Hi Bud,

the resistance measurements from center pins to ground:

MBR20100CT

0.6 Ohms

MBR2045CT

1.7 kOhms

MBR10150CT

infinite

Thanks!

[jetadm123]

Re: Iiyama 2607WS suddenly dead

Looks like something at the output of MBR20100CT is shorted to ground. Which one is the MBR20100CT on your photo?

[formatthias]

Re: Iiyama 2607WS suddenly dead

It's the one on the edge of the board.
What about MBR2045CT? Should be infinite too.

[jetadm123]

Re: Iiyama 2607WS suddenly dead

Guess I should have looked at post #21 concerning the location of MBR20100CT. Anyways, it looks like the center pin of it is connected to two zener diodes, ZD661 and ZD662. Check these two diodes for shorts.

[formatthias]

Re: Iiyama 2607WS suddenly dead

will check it

[formatthias]

Re: Iiyama 2607WS suddenly dead

1.4kohms on both

[jetadm123]

Re: Iiyama 2607WS suddenly dead

There are a cluster of filter caps to the left of the MBR20100CT. Check to see which of these caps have their "+" lead connected to the center pin of the MBR20100CT. Once you have identified the caps, try measuring across each cap for a short.

[formatthias]

Re: Iiyama 2607WS suddenly dead

Did that already. 0.6 Ohms across each of the two caps.

[jetadm123]

Re: Iiyama 2607WS suddenly dead

Suggest you remove those two caps from the board and check them again for shorts.

[budm]

Re: Iiyama 2607WS suddenly dead

MBR20100CT remove this from the baord and it checks OK? And this diode has Isolated TAB or it has isolation pad so it not short to the heatsink which is grounded.

[formatthias]

Re: Iiyama 2607WS suddenly dead

Soldered them out. Still 0.6 Ohms from center pin of 20100 to ground.

[formatthias]

Re: Iiyama 2607WS suddenly dead

will solder 20100 out now

[formatthias]

Re: Iiyama 2607WS suddenly dead

ok, measured 60kohms between pins 1 and 2 and 0.6 Ohms between 2 and 3.

[budm]

Re: Iiyama 2607WS suddenly dead

OK with the Diode out ,measure that center pad on the board, what do you get?
Since it is dual diode with center pin the common Cathode, then you have one diode shorted out.
https://cdn.badcaps-static.com/pdfs/...e20b70f0bf.pdf

[jetadm123]

Re: Iiyama 2607WS suddenly dead

If you reverse the leads of your meter and measure pins 2 and 3 do you still see 0.6 ohms. If yes, then you found your short. Also, since you removed the MBR20100CT, measure the middle empty hole to ground.

budm beat me to it.

[formatthias]

Re: Iiyama 2607WS suddenly dead

Measured infinite without 20100 from center to ground. 0.6 Ohms in both directions, yes.
One of the two is broken.
What about MBR2045?

[jetadm123]

Re: Iiyama 2607WS suddenly dead

I think the MBR2045 is fine, since the resistance of that center pin can be affected by external components connected to it. What is the manufacturer of the caps you removed? Capxon?

[budm]

Re: Iiyama 2607WS suddenly dead

Suggestion when test the component, always remove it from the board to get the true readings.