Samsung Syncmaster 245BW

[Aruba]

Re: Samsung Syncmaster 245BW

I can't find that ic on my board!!!???

This 5 pin IC regulator is mounted to the heatsink that is closest to the two
connectors going towards the logic board. Check the attached picture
(Board.gif) showing where this part is exactly.

[mladen82]

Re: Samsung Syncmaster 245BW

And for Mladen, must be som other thing bad on your monitor to, because this resistor is for protection, go on and test all caps with esr tester for hi esr.

don't have esr tester,
but seems like primary capacitor is slightly bulged, but i don't have such capacitor for replace, dimensions are crucial
however monitor is returned to user
we will see if monitor come back again

[mladen82]

Re: Samsung Syncmaster 245BW

This 5 pin IC regulator is mounted to the heatsink that is closest to the two
connectors going towards the logic board. Check the attached picture
(Board.gif) showing where this part is exactly.

Ooh yes, i saw
thanks

[cloepula]

Re: Samsung Syncmaster 245BW

So, problems with this power supply solved, monitors fixed ...
Only to say in my case was thet resistor, br npn transistor and f9222L. The ice was ok.

[cloepula]

Re: Samsung Syncmaster 245BW

And for esr tester Mladen, you can try esrmicro, from Michail Klikov.
I have one, great tool. Measure esr and capacity off common capacitor. You can try to contact him via badcaps forum, or try to mail him to mike.klykov@gmail.com

[Aruba]

Re: Samsung Syncmaster 245BW

So, problems with this power supply solved, monitors fixed ...
Only to say in my case was thet resistor, br npn transistor and f9222L. The ice was ok.

A couple of questions, first - how did you determine with
what part you were going to replace the "br" transistor with ?
Secondly, where do you get the F9222L part from ?

I think the problem with my unstable 24V is due to the
F9222L controller but I haven't had a chance to replace
the IC yet.

[cloepula]

Re: Samsung Syncmaster 245BW

The br is replaced with "dtc114ts" because i canot find the exactly the same "dtc114te" . The f9222L i found in one electronic shop for 10 euro, and ice3b0365J was 3 euro but in my case was ok so i have one spare now for next repair.

[cloepula]

Re: Samsung Syncmaster 245BW

For f9222L you can try to order from www.elmatis.hr , i found it on ebay to but is 20$ plus postal charges.

[Aruba]

Re: Samsung Syncmaster 245BW

The br is replaced with "dtc114ts" because i canot find the exactly the same "dtc114te" . The f9222L i found in one electronic shop for 10 euro, and ice3b0365J was 3 euro but in my case was ok so i have one spare now for next repair.

Thanks for the information. Did you have a schematic or parts list to tell you
that "br" marked on the transistor package is for a DTC114TS" transistor or
was this an educated guess ?
I found the F9222L and the ICE3B0365J IC at www.dalbani.com located in
Florida. I have a few of each on order as they needed $20 for a minimum
order. Prices were good at less than $4 a piece.

[cloepula]

Re: Samsung Syncmaster 245BW

No, is not a guess, i found br datasheet on the net, and then found a similar component dtc114ts. On this think is not possible to guess. If the component is not the same will not work, and possibly something will burn.

[Aruba]

Re: Samsung Syncmaster 245BW

Ok, I might be a little slow here but you need to educate me and other people. I still
don't understand how you went from knowing the "br" printing on the SMT transistor in
a SOT-23 package to knowing it is equivalent to a DTC114TS part.
Typically one would need at least a few more numbers to know what the part number
is but I would like to know your secret decoder ring you use to go from "br"
to "DTC114TS".

Thanks in advance.

[cloepula]

Re: Samsung Syncmaster 245BW

You go on net, then in google search for "" br sot-23, then will know the br caracteristics, then call som store and ask for a prebiased npn transistor for 50v and 100ma, and two resistor inside 10kohm. components are selected on their caracteristic, and no on their marking codes.

[Aruba]

Re: Samsung Syncmaster 245BW

You go on net, then in google search for "" br sot-23, then will know the br characteristics, then call some store and ask for a prebiased npn transistor for 50v and 100ma, and two resistor inside 10kohm. components are selected on their characteristic, and no on their marking codes.

I see. Although this method might work most of the time it is not foolproof.
While looking for "br sot-23" on Google I also found this spec from NXP
(Philips) for a PNP transistor. One of the versions is marked "br" as described
on the datasheet. As you can see on one hand you find it is a NPN transistor
with pre-biased resistors while someone else might find this to be a PNP
transistor with no pre-biased resistors. I guess for the _majority_ of the time
choosing a NPN type is "safe" but if it still doesn't work and choosing a PNP
type maybe the next step if you don't have anything else to go by.

Thanks for the help.

[cloepula]

Re: Samsung Syncmaster 245BW

I know this, to. It is always possible to find, or almoust always, two or more sugestion on component marking in this way, and without a drowing of a board it is a possibility to make somme wrong ways. In this way you have the chanse to fix the bug on the monitor, there is a possibility thet you will not be a winner yust always. This is the beauty of free artist. There was electronic equipment thet i didnt fix fast, there was alsow equipment thet i gived up. Last 5 lcd monitor was fix in 10-20 minutes, on this i work 20-30 hours in 12 days. Was hard for me to make it work. But now i know more things then before this. Guys from forum shure help me to, and i thanks them all, alot. I hope thet you will solve your problem to.

[Aruba]

Re: Samsung Syncmaster 245BW

I know this, to. It is always possible to find, or almoust always, two or more sugestion on component marking in this way, and without a drowing of a board it is a possibility to make somme wrong ways. In this way you have the chanse to fix the bug on the monitor, there is a possibility thet you will not be a winner yust always. This is the beauty of free artist. There was electronic equipment thet i didnt fix fast, there was alsow equipment thet i gived up. Last 5 lcd monitor was fix in 10-20 minutes, on this i work 20-30 hours in 12 days. Was hard for me to make it work. But now i know more things then before this. Guys from forum shure help me to, and i thanks them all, alot. I hope thet you will solve your problem to.

As the saying goes, you win some, you loose some. The hope is to end up on end up more on the winning side then the losing side. I have some Samsung
LCD TV/monitor schematics but they NEVER show the power supply board
itself as being part of the schematic package. I am not sure why this is but
one would think that it should be part of it as the power supply seems to be
the predominant failure part. The other part is that for a big company as
Samsung is that they would learn from previous mistakes on their design and
their newer design are more reliable but it does not seem to be the case.
Maybe their goal is not to design it more reliable but instead for a good
design at the lowest possible cost. When they calculate the MTBF of the
product and it comes out to 20K hours I think that they get the green light
and manufacture it instead of going back and say to design it for 50K hours.

If the monitor I have also is fixed by replacement of the Fuji Electric F9222L
I would say this part is a high failure rate part on this monitor. I will measure
the resistance and diode voltage measurements between all the pins such
that people can determine if the part is bad when it is desoldered out of the
board.

[cloepula]

Re: Samsung Syncmaster 245BW

So, did you solve the bug Aruba ??

[Aruba]

Re: Samsung Syncmaster 245BW

So, did you solve the bug Aruba ??

Not yet, I am still waiting for the parts to come in. If they left their
destination last Friday they should come in in the next couple of days.
May I ask where you are located ? I'm guessing somewhere in Eastern Europe.

[stewart710]

Re: Samsung Syncmaster 245BW

Well, I'm really happy that you got your LCD working again. I will have to find a way to order the IC and transistor and repair mine. Thanks for wrapping this one up.

[cloepula]

Re: Samsung Syncmaster 245BW

I m located in Croatia, city Pula. And Aruba, i m not a genius of electronic, but maybe this will help you a little : When you chosing pnp, or npn transistor, you must consider where this transistor is located in circuit, and how is conected. If load is conected to transistor colector and is emiter is conected to ground in somme way then this must be npn transistor. And if power line is conected to transistor colector, and emiter is going to the load, then its is pnp transistor. Using this simple rule is sometime the only way to determine the right transistor for replacing burned one.

[lucky13]

Re: Samsung Syncmaster 245BW

I am following this thread with interest as I have two of these P/S in my possession but no monitor to test them in.

One flickers badly as the 24V rail is jumping up and down.

The other has only the standby voltage and nothing else.

Quick check the obvious posted regarding the burnt resistor and BR transistor seem to be not the problem with these.

Back to lurking....