Replacing a Current Sense Resistor

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  • Darren Hibbert
    Senior Member
    • Feb 2024
    • 102
    • UK

    #1

    Replacing a Current Sense Resistor

    Hi.

    Quick question.

    I have a laptop that is completely dead. I opened it up and it looks like the current sense resistor is blown. However, because it's blown, the value printed on the top has disintegrated and there is no schematic available for this particular laptop (Dynabook Portege) so I'm not sure what to replace it with.
  • Darren Hibbert
    Senior Member
    • Feb 2024
    • 102
    • UK

    #2
    Anyone?

    Comment

    • mon2
      Badcaps Legend
      • Dec 2019
      • 14106
      • Canada

      #3
      Locate the charger ic and then a reference schematic that uses the same controller. This board most likely will use the same current sense resistor. Design engineers like to follow proven reference designs.

      Have to say that it is rare for the current sense resistor to burn out.

      Comment

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