Samsung 245B diode question

[shaynet]

Hi All. :-)
I have a Samsung 245B in pieces on my workbench. It has been there for about 6 months now and I think it is probably about time I reclaimed that space. lol The reason it is there is because I gave up trying to identify a diode on it. The diode is "DM804". It is shorted and I want to get a new one but can't see any markings on it. Can anyone give me a part number for it so I can buy one?
Thanks very much! :-)

[ben7]

Re: Samsung 245B diode question

Hi All. :-)
I have a Samsung 245B in pieces on my workbench. It has been there for about 6 months now and I think it is probably about time I reclaimed that space. lol The reason it is there is because I gave up trying to identify a diode on it. The diode is "DM804". It is shorted and I want to get a new one but can't see any markings on it. Can anyone give me a part number for it so I can buy one?
Thanks very much! :-)

You sure you can't see any markings? Is it smd?

[budm]

Re: Samsung 245B diode question

What is model number of the board? There are at least two versions of the power supply board in this model.

[shaynet]

Re: Samsung 245B diode question

You sure you can't see any markings? Is it smd?

Oops, sorry. I meant to put the numbers. The diode is a leaded part, not smd. On the diode is: S4 76.
I searched high and low but can't find any info on any diode with that marking.

Thanks!

[shaynet]

Re: Samsung 245B diode question

What is model number of the board? There are at least two versions of the power supply board in this model.

On the board it says:

Made in Korea
Model: HUB24P

This number is also on the board: BN44-00173A

Thanks!
:-)

[budm]

Re: Samsung 245B diode question

Here is the diagram of the board from Tom's web site.

[shaynet]

Re: Samsung 245B diode question

Here is the diagram of the board from Tom's web site.

Thanks. That is the schematic I am using. Unfortunately it doesn't help me with a part number for the diode. I suppose I could just stick in any schottky diode and see what happens.

[euromatlox]

Re: Samsung 245B diode question

Using google image search for 'F9222L' you can find a diagram where pin 4 is connected into ground with two resistors and diode D1FS4 (40V 1.1A Schottky Barrier Diode).

[shaynet]

Re: Samsung 245B diode question

Using google image search for 'F9222L' you can find a diagram where pin 4 is connected into ground with two resistors and diode D1FS4 (40V 1.1A Schottky Barrier Diode).

Thanks! That should be just what I'm looking for!

[jetadm123]

Re: Samsung 245B diode question

If you type "S4 diode" in the eBay search box, you'll get listings for a 1N5819 Schottky diode rated @ 40V 1A as suggested by euromatlox.

[budm]

Re: Samsung 245B diode question

By the way, did you test that DiODE DM804 off the board, since it is connected in parallel with the MOSFET Q1 Source resistor RM803 (0.39 Ohms) it will show very low resistance reading.
The three 68 Ohms resistors are OK? All the glues are removed?

[shaynet]

Re: Samsung 245B diode question

By the way, did you test that DiODE DM804 off the board, since it is connected in parallel with the MOSFET Q1 Source resistor RM803 (0.39 Ohms) it will show very low resistance reading.
The three 68 Ohms resistors are OK? All the glues are removed?

Sure did! Pulled it and checked it. Dead short. The 68 ohm resistors are all good. I also have replaced RM801 (.22 ohm). It was a sneaky one. It looked perfect from the top. Not even discolored, but there was a nice black hole on the side I couldn't see.
Diode is ordered. Hopefully it will arrive this week.

[californiak]

Re: Samsung 245B diode question

I just found the very same blown resistor RM801 with the big hole on the bottom side blown out... do you think it had something to do with the diode DM 804 being shot? and finally did you fix the 193A PS and is it working good with the replacement diode? Thanks

[kicku]

Re: Samsung 245B diode question

Here is the diagram of the board from Tom's web site.

Thank you for schematic.