smps transformer

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Ashroyer05
    Senior Member
    • Sep 2013
    • 162
    • U.S

    #1

    smps transformer

    in standby does the main transformer run? If so does the transformer put out more voltage when the smps is in full operation?
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: smps transformer

    The transformer does not usually run. Big transformers have a minimum magnetising current required to operate properly, which means they are generally inefficient and this would consume too much power. Legal requirement in EU is now less than 0.5W in standby.
    Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
    For service manual, schematic, boardview (board view), datasheet, cad - use our search.

    Comment

    • 370forlife
      Large Marge
      • Aug 2008
      • 3112
      • United States

      #3
      Re: smps transformer

      If the power supply is like a computer SMPS, there is kind of a second, smaller power supply that runs the 5V stand by circuit. Its generally a very simple two transistor setup on a cheaper unit, or a discrete IC, that has a low current rating. The 5V stand by circuit has its own, small, transformer.

      Comment

      Related Topics

      Collapse

      • denisten
        Sony STR-DB870QS standby transformer
        by denisten
        Hi everyone, i am a newbie here and i hope i will find the help i need. I have the above mentioned receiver with standby transformer's primary coil damaged. I have searched the net without success to find any tech data about this transformer. I have only the Sony part number1-437-313-11 and TAM Malaysia M0126. I guess i could find replacement for it, but i need to know the secondary coil voltages and VA. It is 220v on the primary. It has 5 pins on the secondary, the outer two are not used and i have 6.5 ohms between pins 2and 4, 3,9 ohms between 2 and 3, and 3,6 ohms between 3 and 4. Can someone...
        04-14-2023, 03:24 AM
      • Hounddoghill
        DPS285BP 5v standby transformer blown
        by Hounddoghill
        Sharp TV LC-80LE633U
        Power supply board DPS 285BP Run TKB096WJQZ

        Standby transformer markings (attached picture)
        MP-130I(01)
        AV-DP11153 Delta
        Dcum 1244(03) H6P

        So an event in the primary exploded the cap (C7901)on pin one of the Standby circuit IC. So after replacing a couple diodes a the 2.2ohm resistor(fuse) I found the transformer inputs are open.

        Anyone know about replacements for this transformer?
        I suspect the original is not available.
        https://www.badcaps.net/forum/images/smilies/silly.gif
        ...
        02-04-2022, 03:22 PM
      • tvguy12012012120
        Zombie Samsung UN55NU6900F dead / no standby voltage - randomly came to life after hours of troubleshooting then died
        by tvguy12012012120
        This is my first attempt at troubleshooting a board like this, I know I could just buy a new board but I'm curious to figure out how this works. I've been testing different components in the evenings this week and I think the problem is with the IC failing to start up for some reason. When the board is plugged in there is no standby voltage.

        Then today it randomly sprung to life like a zombie but shortly died thereafter. I have no idea why it would have done that and its the first time I've seen it running. I discharged capacitors on the board last night, then it was sitting today....
        02-07-2025, 05:13 PM
      • Briesmith
        Can High Side damage on an SMPS get across the Transformer to the Low Side?
        by Briesmith
        I have a blown smps and I am looking for some reassurance as to the amount of diagnosis I have to do. It blew the instant I plugged it in not under any load.

        As you can see from the attached pix, the damage is located around the main or bulk capacitor (since removed for testing) and the resistor array/network that drives it (the bunch of SMD components to the left of the YAMAHA YC775 AMPS logo). The burn mark on the frame clearly shows the pins of the capacitor. And, for the avoidance of doubt, there is no way the board could have contacted the frame, it was correctly mounted on...
        05-06-2023, 09:36 AM
      • mikey5791
        Is it possible for transformer substitution?
        by mikey5791
        Hi all,
        Got this local made DC power supply (12/14V) given free as the transformer has melted. There is no marking or indication to identify what type or rating of transformer used.
        Fyi,. I had a busted autogate mainboard with transformer with marking 13-0-13 . Is this the 13v dc type transformer?
        My questions are
        1. How do i test to see if the transformer is in good working condition?
        2. Can this transformer (marking 13-0-13) be used to replace the melted transformer on the DC power supply?
        Hope you guys understand what i was asking. My intention is...
        11-03-2022, 02:11 AM
      • Loading...
      • No more items.
      Working...