Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why Phone Charger Makes High Frequency Sound

  1. May 20, 2012 #1
    Hi. I noticed that my phone charger (output: 5V DC) makes a constant high pitched noise when plugged into the wall. It's not too loud but you can hear it when you are within maybe 4 ft of the charger. When I plug my phone in, it starts making intermittent noises. I was wondering what this could be caused by?
     
  2. jcsd
  3. May 20, 2012 #2
    Most charges are using switching regulators, they oscillates in 10s of KHz, you can hear it if the transformer buzzes.
     
  4. May 20, 2012 #3
    does that mean there is current flow and thus energy loss even without the phone attached?
     
  5. May 20, 2012 #4
    Yes, there is always a little loss if you keep the charger plugged in.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Why Phone Charger Makes High Frequency Sound
  1. Cell Phone Charger (Replies: 3)

Loading...