IP-24135A power board parts ID Samsung 510n

[UniT3d]

Hey there everyone,

This samsung unit has no backlight. All capxons were removed for replacement. I was inspecting the board during caps removal and found a burnt part D205. I'm having trouble reading the markings for D205 on this power board (IP-24135A). If anyone has any info on it, kindly let me know the part number.

I'm also interested to know what would be the part number for Q201. The original part number is IRFR5505 and I've read a post elsewhere that SFR9034 was also used for Q201 on some boards.

Any help is much appreciated.

[UniT3d]

Re: IP-24135A power board (Samsung 510n) parts ID

Finally acquired some FR5505 for replacement. All necessary caps was already replaced. Pico fuse also replaced. I still don't know what is D205 part number (however, even though it looks burnt, apparently it still works. Tested ok with a meter and also as per below). I still wish I know what D205 is and get it replaced.

I took the plunge and power it up. Hey hey! it works, it works. Secondary voltages (5v & 13v) are correct. Backlight works good. Will now go through a few days of usage to see how it goes.

I have a question for the masters here. For capacitors used in parallel, the capacitance is added up but is this also true for current ripple ?

Thanks.

[Longbow]

Re: IP-24135A power board (Samsung 510n) parts ID

For capacitors used in parallel, the capacitance is added up but is this also true for current ripple ?

Add the uf value of capacitors in parallel. Second part of your question is not specific enough. Let's say 2 1000 uf filter caps are in parallel. Then it is obvious that they needed more than 1000 uf for the design, but didn't have the room for a large part, or else they got a good deal on 1000 uf caps. In this case 2000 uf will filter the line better than 1000 uf, but exactly how much better is not predictable. Second example; 1000 uf in parallel with .1 uf ceramic. Total capacitance is 1000.1 uf but the value itself is not important. The purpose of the .1 uf is to filter high frequency (in this case maybe > 1 MHz) and a ceramic cap will do it better (lower ESR @ 1 MHz and above) than the 1000 uf capacitor. What could be simpler than that?

[PlainBill]

Re: IP-24135A power board (Samsung 510n) parts ID

<SNIP>

I have a question for the masters here. For capacitors used in parallel, the capacitance is added up but is this also true for current ripple ?

Thanks.

Yes, sort of. Assume two identical capacitors, each rated for 1.3A ripple current. In parallel they could handle a total of 2.6A ripple current.

However, we are in the real world. One capacitor will have a slightly higher capacitance than the other, one capacitor will have a slightly lower ESR than the other, so they won't share the current equally. Thus the maximum current they could handle would be slightly less than 2.6A.

However, we are in the real world. Circuits are not designed so a component is working at it's limits.

PlainBill

[UniT3d]

Re: IP-24135A power board (Samsung 510n) parts ID

Hmmm .....

Thanks for the inputs from both of you, Longbow and PlainBill. I learned something new everyday.

Update on the Samsung 510n, the backlight became intermittent on power ups. I looked at the board again and gently pressed the board around the transformers. There's one spot when pressed turns the backlight back on. So, I resoldered what seems to be cold joints on the resistor beside the pico fuse and also did the same for the transformers. Seems to fix the intermittent issue.

[Longbow]

Re: IP-24135A power board (Samsung 510n) parts ID

Yes, sort of. Assume two identical capacitors, each rated for 1.3A ripple current. In parallel they could handle a total of 2.6A ripple current.
PlainBill

Could you please enlighten me about this statement? Where is it written down that a particular capacitor is rated @ 1.3A ripple current? Is this number published by the capacitor manufacturer, or does it refer to the load current connected to the supply?

Thanks!

[PlainBill]

Re: IP-24135A power board (Samsung 510n) parts ID

Could you please enlighten me about this statement? Where is it written down that a particular capacitor is rated @ 1.3A ripple current? Is this number published by the capacitor manufacturer, or does it refer to the load current connected to the supply?

Thanks!

Ripple current is often one of the published specs for low ESR capacitors. For example, the Panasonic EEU-FM1V221 datasheet shows a rated ripple current of 1.29 amp.

PlainBill

[Longbow]

Re: IP-24135A power board (Samsung 510n) parts ID

Thanks. That information is valuable, especially if you are the power supply designer, or looking for suitable replacement caps. My only comment is that I've never had to check on this info to fix a power supply problem, but maybe I should have since there are so many sub-standard parts available. I'll go out on a limb and make a guess that there's no way to quantify the result of putting 2 or more caps in parallel with different ripple current specs. In earlier times, we called it "ampacity", but that was before the days of high current low voltage switching supplies.

[PlainBill]

Re: IP-24135A power board (Samsung 510n) parts ID

Thanks. That information is valuable, especially if you are the power supply designer, or looking for suitable replacement caps. My only comment is that I've never had to check on this info to fix a power supply problem, but maybe I should have since there are so many sub-standard parts available. I'll go out on a limb and make a guess that there's no way to quantify the result of putting 2 or more caps in parallel with different ripple current specs. In earlier times, we called it "ampacity", but that was before the days of high current low voltage switching supplies.

You are right, there is no way to quantify the results. I maintain it isn't necessary because an isolated failure of an electrolytic capacitor is very rare. When you open up a monitor and see 4 Capxon, Ltec, or Elite caps in parallel, with one of them vented, two bulging and one looking normal, common sense says that one has totally failed, two are in the process of failing, and the last isn't any good, either. The only sensible thing to do is replace all four of them.

To a certain extent, the following can be modified, depending on circumstances, but when I repair a monitor, odds are I intend to sell it. I value my reputation, so I won't sell something unless I believe I have done everything reasonable to make sure a repaired monitor will last a long time. And if that means replacing ALL the low ESR electrolytic caps in the power supply, I will do it.

Let's face it, the biggest expense of repairing a monitor is the time involved. And a major part of the time is spent pulling the silly thing apart!! Saving $.78 by not replacing a Capxon cap whose neighbors are all bulging doesn't make any sense.

PlainBill

[kekchiew]

Re: IP-24135A power board parts ID Samsung 510n

D205 part number is B3- dual channel schottky diode and Q201 part number is SFR9034- power mosfet. May i know the value of C111 and C112?

[UniT3d]

Re: IP-24135A power board parts ID Samsung 510n

Hmmm .....

No longer have the board. According to my old notes, C111 + C112 should be 680uf 25v (originally Capxon KM). Nichicon HE was a nice replacments for these.

[Hobb1e5t]

Re: IP-24135A power board parts ID Samsung 510n

Hi@all
i have Samsung 510N but with different Power/Invertor Board.
it has PCB Code FSP025-2PI01

On INvertor side of PCB there are 2 SMD Transistors marked as DK QQ . One of them is heated up and C22 (Blast Cap) is also burnt.

Can anyone tell me Replacement Part code for DK-QQ , ant datasheet for the same?
or
Can anyone help me to get Samsung 510N SM with Circuit Diagrame
THanks
REgards