Samsung 713N with IP-35135A PS, no 5VDC

[kckcap]

I've got a samsung 713N with the IP-35135A power supply. Looks to be a common supply with Dells, etc. Initially I had no power indications, no led status,etc. I found some obviously bad caps on the PS and replaced them. The following were replaced (2) 820uf, (2) 1000uf and (1) 330uf.

After replacement of the above caps the monitor status led is now rapidly blinking green. I checked for voltages and found I have only 1.4 VDC on both the 5VDC and 13VDC pins that come out of the PS going to the video board.

Without a schematic I'm a little lost as to what to check next. I've attached a pic of the ps and have circled the caps I replaced.

Thanks

[PlainBill]

Re: Samsung 713N with IP-35135A PS, no 5VDC

I've got a samsung 713N with the IP-35135A power supply. Looks to be a common supply with Dells, etc. Initially I had no power indications, no led status,etc. I found some obviously bad caps on the PS and replaced them. The following were replaced (2) 820uf, (2) 1000uf and (1) 330uf.

After replacement of the above caps the monitor status led is now rapidly blinking green. I checked for voltages and found I have only 1.4 VDC on both the 5VDC and 13VDC pins that come out of the PS going to the video board.

Without a schematic I'm a little lost as to what to check next. I've attached a pic of the ps and have circled the caps I replaced.

Thanks

https://www.badcaps.net/forum/showthread.php?t=1868 I'm petitioning Dante to add a tenth circle for people who embed pictures in their posts.

1.4 volts is unusual. The question is the SMPS current limiting, or is there another fault. The SMPS controller / switch is the 4 (5?) pin IC attached to the heat sink bottom center. Look up the part number and download the data sheet. CAREFULLY!! check the voltage across the large cap. That might give a clue. Check the voltages on the pins of the controller. Check for shorts in the load - in particular, shorted drivers in the inverter.

PlainBill

[Toasty]

Re: Samsung 713N with IP-35135A PS, no 5VDC

>>I'm petitioning Dante to add a tenth circle for people who embed pictures in their posts.<<
Amen! ...and pass the ammunition!

@kckcap:
Replace the other 3 small caps in the lower part of the picture.

[kckcap]

Re: Samsung 713N with IP-35135A PS, no 5VDC

Voltage on the big cap = 161vdc From what I've read on this forum the voltages should be over 350vdc?
The SMPS controllers part number is DM0565R, I'm trying to find a spec sheet on it now.

Sorry about the embedded pic. I did read the thread on photos and I thought that how I did it was the way the forum admin wanted it.

[kckcap]

Re: Samsung 713N with IP-35135A PS, no 5VDC

I also can hear a very faint, steady 'snapping' sound from the ps. Probably about 4 or 5 'snaps' per second The room has to be absolutely quiet but I can definitely hear it. Its too faint to be able to tell what exact component is doing it and I'm not going to press my ear too close to the big cap.

[PlainBill]

Re: Samsung 713N with IP-35135A PS, no 5VDC

I also can hear a very faint, steady 'snapping' sound from the ps. Probably about 4 or 5 'snaps' per second The room has to be absolutely quiet but I can definitely hear it. Its too faint to be able to tell what exact component is doing it and I'm not going to press my ear too close to the big cap.

Good ears. It's a good chance that's the SMPS starting up. Follow Toasty's advice. If that fixes it, Toasty gets an 'Attaboy'.

PlainBill

[Radio Fox]

Re: Samsung 713N with IP-35135A PS, no 5VDC

Voltage on the big cap = 161vdc From what I've read on this forum the voltages should be over 350vdc?...

The voltage on the big cap comes from the rectified & smoothed mains voltage.

If you are in a country with 120V mains you will get in the region of 165V, and around 330V in a country with 240V mains.

One of the many reasons to fill in your location in your profile.

[kckcap]

Re: Samsung 713N with IP-35135A PS, no 5VDC

Thanks for all the advice. I'm going to order the remaining caps and let everyone know how it works.

[kckcap]

Re: Samsung 713N with IP-35135A PS, no 5VDC

I replaced the three remaining caps with no luck. Still no 5VDC and the 'snapping' sound remains. Maybe replace the SMPS? But if its the component 'snapping' I think it may be working correctly and turning on/off due to another component 'overdriving' it.

[wafik]

Re: Samsung 713N with IP-35135A PS, no 5VDC

will you please help me with my problem, ive got the same power supply board but the smps main primary switcher is totally burnt i cant find the value please if u can provide me wit the full part number so i can replace it thank you

[wafik]

Re: Samsung 713N with IP-35135A PS, no 5VDC

any reply?

[dacianh28]

Re: Samsung 713N with IP-35135A PS, no 5VDC

have the same problem, did you find a solution?
thanx

[Scenic]

Re: Samsung 713N with IP-35135A PS, no 5VDC

sounds like a short on the secondary side somwehere..

PSU trying to start up, detects a short, shuts down, repeat
(would explain the "snapping" sound)

whenever i come across a monitor with these symptoms, i replace all caps except the 400-450V one, and check the diodes/diode packs on the secondary side for shorts..

[dacianh28]

Re: Samsung 713N with IP-35135A PS, no 5VDC

thank you for the fast post, i will check the diodes then see if those are the problem.

[dacianh28]

Re: Samsung 713N with IP-35135A PS, no 5VDC

i've checked all the diodes, all good, don't know what to do next...

[PlainBill]

Re: Samsung 713N with IP-35135A PS, no 5VDC

i've checked all the diodes, all good, don't know what to do next...

One approach is to provide 5V and 12V to the outputs of the power supply. (Do this with the logic board disconnected). If you hook 3 AA penlight cells in series from ground (-) to the +5V output and read approximately 4.5 volts, there is no excessive load. You can use the same batteries to test the 12V output, or use a 9V battery.

If neither of these showed a problem, try testing the supply with no logic board connected.

PlainBill

[dacianh28]

Re: Samsung 713N with IP-35135A PS, no 5VDC

i plugged in with the logic board disconnected, and i started to see some smoke, and after i checked the psu board on the back i saw that the SP8M3 smd with 8 legs has a small ash in a corner. probably that smd was the problem from the start. now i have to search for a replacement.

[dacianh28]

Re: Samsung 713N with IP-35135A PS, no 5VDC

worked. replaced the two SP8M3 and it's good as new
thanks all for your help.

i plugged in with the logic board disconnected, and i started to see some smoke, and after i checked the psu board on the back i saw that the SP8M3 smd with 8 legs has a small ash in a corner. probably that smd was the problem from the start. now i have to search for a replacement.

[stepgr]

Re: Samsung 713N with IP-35135A PS, no 5VDC

Hi newbie here
where can I find (buy europe if possible) those SP8M3 ? I also have a couple of 920N with
bad caps and after the replacement of the capacitors one of these
two ic's burned. Also are there any tips for SMD's it's my first time
to deal with such components.

[PlainBill]

Re: Samsung 713N with IP-35135A PS, no 5VDC

Hi newbie here
where can I find (buy europe if possible) those SP8M3 ? I also have a couple of 920N with
bad caps and after the replacement of the capacitors one of these
two ic's burned. Also are there any tips for SMD's it's my first time
to deal with such components.

There are several approaches to removing SMD components, my favorite is a product called Chip-Quik. It forms a low melt point alloy that allows you to simply lift the IC. You must clean up the residue with solder braid. A kit runs about $15.

Another is to use a hot air rework station, but those cost a bit more.

A third approach requires a bit of dexterity and a pair of cutters with very small tips. Melt the solder on a pin, then clip the pin at the body of the IC. Repeat.

There are 21 sellers on eBay offering these ICs. The going rate appears to be 5 for $6.00 with free 'worldwide' shipping. Unfortunately, significant areas of the world are excluded. One list is rather extensive.

Item location: Yueqing, Zhejiang, China
Shipping to: Worldwide
Excludes: New Zealand, Fiji, Papua New Guinea, Guadeloupe, Marshall Islands, Wallis and Futuna, Gambia, Malaysia, Mayotte, Taiwan, Poland, Suriname, Oman, Kenya, United Arab Emirates, Argentina, Middle East, Guinea-Bissau, Togo, Senegal, Armenia, Bhutan, Uzbekistan, Ireland, Qatar, Falkland Islands (Islas Malvinas), Netherlands, Burundi, Slovakia, Iraq, Equatorial Guinea, Slovenia, Thailand, North America, Aruba, American Samoa, Sweden, Iceland, Macedonia, Liechtenstein, Israel, Kuwait, Belgium, Algeria, Benin, Russian Federation, Oceania, Antigua and Barbuda, Italy, Swaziland, Pakistan, Tanzania, Ukraine, Singapore, Panama, Burkina Faso, Jersey, Kyrgyzstan, Switzerland, Reunion, Djibouti, Chile, China, Mali, Croatia, Republic of, Botswana, Cambodia, Portugal, Indonesia, Malta, Tajikistan, Vietnam, Paraguay, Cayman Islands, Saint Helena, Cyprus, Rwanda, Seychelles, Australia, Bangladesh, Austria, Zimbabwe, Gabon Republic, Bulgaria, Czech Republic, Cote d Ivoire (Ivory Coast), Norway, Kiribati, Turkmenistan, Greece, Grenada, Haiti, Greenland, Yemen, Afghanistan, Montenegro, Africa, Mongolia, Nepal, Bahrain, Bahamas, Svalbard and Jan Mayen, United Kingdom, Dominica, Hungary, Bosnia and Herzegovina, Angola, South America, Southeast Asia, Western Samoa, France, Mozambique, Namibia, Peru, Guatemala, Denmark, Vatican City State, Solomon Islands, Sierra Leone, Nauru, French Guiana, Anguilla, El Salvador, Guam, Micronesia, Dominican Republic, Cameroon, Guyana, Azerbaijan Republic, Macau, Georgia, Tonga, New Caledonia, San Marino, Eritrea, Saint Kitts-Nevis, Morocco, Saint Vincent and the Grenadines, Belarus, Europe, Mauritania, Belize, Philippines, Uruguay, Congo, Democratic Republic of the, Western Sahara, Congo, Republic of the, French Polynesia, Cook Islands, Colombia, Comoros, Spain, Estonia, Bermuda, Montserrat, Korea, South, Zambia, Somalia, Vanuatu, Ecuador, Albania, Monaco, Guernsey, Ethiopia, Laos, Niger, Venezuela, Ghana, Cape Verde Islands, Martinique, Moldova, Saint Pierre and Miquelon, Madagascar, Lebanon, Liberia, Bolivia, Maldives, Gibraltar, Libya, Hong Kong, Central African Republic, Lesotho, Nigeria, Saint Lucia, Mauritius, Guinea, Jordan, Canada, British Virgin Islands, Turks and Caicos Islands, Chad, Andorra, Romania, Costa Rica, India, Mexico, Serbia, Kazakhstan, Netherlands Antilles, Saudi Arabia, Japan, Lithuania, Trinidad and Tobago, Palau, Malawi, Nicaragua, Finland, Tunisia, Luxembourg, Uganda, Brazil, Turkey, Barbados, Germany, Tuvalu, Jamaica, Latvia, Egypt, Niue, Brunei Darussalam, Honduras, Virgin Islands (U.S.), South Africa

PlainBill