Vs grounded on Lower X-buffer?

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • bigmatt0211
    Member
    • Dec 2015
    • 44
    • United States
    #1

    Vs grounded on Lower X-buffer?

    When I check continuity on my lower X-buffer board, the Vs seems to be grounded. Is this normal? When I connect the power supply to it, the Vs goes to ground. I don't see any causes.

    I have a Samsung PN51E530A3FXZA that won't turn on, but I have a seperate thread for that.
    Tags: None
    • bigmatt0211
      Member
      • Dec 2015
      • 44
      • United States
      #2
      Re: Vs grounded on Lower X-buffer?

      Does this sound normal to anyone?

        Comment

        • ReeceyBurger123
          Never Give Up !
          • May 2014
          • 7325
          • Britain
          #3
          Re: Vs grounded on Lower X-buffer?

          Checked Ymain for S/C common issue on these ?
          Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

          https://www.facebook.com/Telford-Tel...7894576335359/

            Comment

            • bigmatt0211
              Member
              • Dec 2015
              • 44
              • United States
              #4
              Re: Vs grounded on Lower X-buffer?

              Well this is just the Lower X-buffer completely disconnected from any other circuit. Vs has direct continuity to ground.

                Comment

                • bigmatt0211
                  Member
                  • Dec 2015
                  • 44
                  • United States
                  #5
                  Re: Vs grounded on Lower X-buffer?

                  Alright, now that the forum is back up, I can continue! Reecey, thank you for your help so far. I really hope we can get this thing figured out.

                    Comment

                    • ReeceyBurger123
                      Never Give Up !
                      • May 2014
                      • 7325
                      • Britain
                      #6
                      Re: Vs grounded on Lower X-buffer?

                      Ok take the Xmain out it has some Smd mosfets on the underside possibly them shorted.
                      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

                      https://www.facebook.com/Telford-Tel...7894576335359/

                        Comment

                        Previous template Next

                        Related Topics

                        Collapse
                        • repair-it
                          Trying to determine a fault, not sure if the culprit is LM2574 pin 7 output is grounded
                          by repair-it
                          I'm not sure if this is correct, the output pin 7 is grounded or the ic has a short. I'm just trying to rule it out. https://www.ti.com/product/LM2574?qgpn=lm2574
                          07-14-2025, 02:03 PM
                        • danny34
                          Thinkpad E15 Gen2 Intel "lower wattage AC Adapter"
                          by danny34
                          Hello folks,

                          My Thinkpad E15 Gen2 with i7 had stopped loading and wouldn't start either. I noticed the typical error with the Mosfet QB6. This has become unsoldered.

                          I soldered it back on and found that the gate voltage was too low and that's why it was getting hot. Then I wanted to replace the UB7. Unfortunately the one I ordered from China didn't want to run.
                          So I soldered the old one back in and it still has its 18.9V at the output of QB6.
                          I stuck a thermal pad on the QB6 to cool it down a bit.

                          Now the E15 is running again, but unfortunately...
                          10-30-2024, 02:10 AM
                        • Adenitz
                          Electronics failing when supplied with lower voltage
                          by Adenitz
                          Hello guys,
                          recently I watched Richard's video on YT (Learn Electronics Repair channel) with an explanation why lower input voltage than rated can also kill electronics components.
                          The vide can be shown here.

                          Now, I would like to learn more and I'm not sure that I understood exactly why this is happening.
                          It is clear to me that PWM chip will keep MOSFTES switched On longer (duty cycle is longer) and that they will dissipate more heat. I think this is not the main reason because MOSFET can probably work switched on for a long time. It is also possible that output...
                          12-26-2022, 12:45 AM
                        • warsztat
                          Lenovo T480s "AC adapter has a lower wattage"
                          by warsztat
                          Hi, Lenovo T480s displays a message : The connected AC adapter has a lower wattage than the recommended AC adapter..."
                          AC adapter is ok. Other power supplies with a power of at least 45W and more were connected without success. The message is the same. The battery is charged when the laptop is turned off. The laptop without a battery connected to the power supply does not start, the power button LED lights up 3 times and nothing else. I don't have a laptop yet, the power socket is USB-C, so I don't know what voltage the power supply supplies when connected to the laptop. There was a...
                          02-12-2024, 05:22 AM
                        • KYBOSH
                          Samsung UN55HU8550F - No picture, No sound
                          by KYBOSH
                          Previous owner says this unit powers on and sometime has an image and sometimes not. They attempted to replace the main board but with no success.

                          TV came with the replacement mainboard as well as the original.

                          When the TV turns on there is no image or sound. No response to the remote or toggle button other than the power button. The power supply's relay was clipping here and there. It did that for several seconds even after I removed the mains. I did this even with no other boards connected (only the backlight was connected at the time). Backlight looks fine but...
                          01-09-2023, 02:36 PM
                        • Loading...
                        • No more items.
                        Working...