The Notebook Review forums were hosted by TechTarget, who shut down them down on January 31, 2022. This static read-only archive was pulled by NBR forum users between January 20 and January 31, 2022, in an effort to make sure that the valuable technical information that had been posted on the forums is preserved. For current discussions, many NBR forum users moved over to NotebookTalk.net after the shutdown.
Problems? See this thread at archive.org.

    Reverse Charging?

    Discussion in 'Sager and Clevo' started by emike09, Feb 5, 2009.

  1. emike09

    emike09 Overclocking Champion

    Reputations:
    652
    Messages:
    1,840
    Likes Received:
    0
    Trophy Points:
    55
    So I've got a USB charger that outputs 500mAh into a USB cable. I'm wondering if I plugged my laptop into that, if it would charge the battery. I'd imaging it would take a friggin long time to charge, but I wonder. Any thoughts?
     
    emike09, Feb 5, 2009
    #1
  2. Hirohata

    Hirohata GBF Danchou

    Reputations:
    492
    Messages:
    1,071
    Likes Received:
    1
    Trophy Points:
    56
    I don't think I've seen a laptop charge via USB before. Serious note, how are you connecting your laptop to charge again? 500mAh seems a bit low for powering a laptop eitherway.
     
    Hirohata, Feb 5, 2009
    #2
  3. Johnksss

    Johnksss .

    Reputations:
    11,536
    Messages:
    19,464
    Likes Received:
    12,852
    Trophy Points:
    931
    that's a big no emike.
     
    Johnksss, Feb 5, 2009
    #3
  4. whizzo

    whizzo Notebook Prophet

    Reputations:
    769
    Messages:
    5,851
    Likes Received:
    2
    Trophy Points:
    206
    a very, very big no.
     
    whizzo, Feb 5, 2009
    #4
  5. Gophn

    Gophn NBR Resident Assistant

    Reputations:
    4,843
    Messages:
    15,707
    Likes Received:
    3
    Trophy Points:
    456
    theres no DC connectivity between the USB power to the Motherboard/Battery power.... so there is no reverse charging.
     
    Gophn, Feb 5, 2009
    #5
  6. Johnksss

    Johnksss .

    Reputations:
    11,536
    Messages:
    19,464
    Likes Received:
    12,852
    Trophy Points:
    931
    off topic: since im not going to chase gophn around the forums. :D :)

    how much money do "we" have for "my" new laptop??

    lol

    on topic...

    it's still a big no..
     
    Johnksss, Feb 5, 2009
    #6
  7. scourge18a

    scourge18a Notebook Consultant

    Reputations:
    32
    Messages:
    208
    Likes Received:
    0
    Trophy Points:
    30
    How about the Buy Scourge A Quadcore charity?
     
    scourge18a, Feb 6, 2009
    #7
  8. Gophn

    Gophn NBR Resident Assistant

    Reputations:
    4,843
    Messages:
    15,707
    Likes Received:
    3
    Trophy Points:
    456
    last I checked... $5. :)

    only been one and only one donor.... more than I could have imagined actually. :D
     
    Gophn, Feb 6, 2009
    #8
  9. Hirohata

    Hirohata GBF Danchou

    Reputations:
    492
    Messages:
    1,071
    Likes Received:
    1
    Trophy Points:
    56
    So there's only been me eh? Come on people. Let's get Gophn something new. He deserves it~ ;)
     
    Hirohata, Feb 6, 2009
    #9
  10. Bill F

    Bill F Notebook Consultant

    Reputations:
    8
    Messages:
    107
    Likes Received:
    0
    Trophy Points:
    30
    You could probably build a circuit that would charge the battery directly through USB.
    However I think you would need to step the voltage up some.
     
    Bill F, Feb 6, 2009
    #10
  11. Shyster1

    Shyster1 Notebook Nobel Laureate

    Reputations:
    6,926
    Messages:
    8,178
    Likes Received:
    0
    Trophy Points:
    205
    How long have you had the PayPal account set up?
     
    Shyster1, Feb 6, 2009
    #11
  12. Cookie

    Cookie Notebook Evangelist

    Reputations:
    32
    Messages:
    527
    Likes Received:
    0
    Trophy Points:
    30
    The NP5797 requires up to 6A @ 20V under full load (battery charging + cpu/gpu fully stressed). Under normal use (web-surfing) I'd guess it uses about 2-3A @ 20V. That's 40-60W. Good luck drawing 60W from a USB-outlet. You'd probably melt the usb-port, as they are only designed for 2,5W (0,5A @ 5V)
     
    Cookie, Feb 6, 2009
    #12
  13. Gophn

    Gophn NBR Resident Assistant

    Reputations:
    4,843
    Messages:
    15,707
    Likes Received:
    3
    Trophy Points:
    456
    the Paypal donate button has been up since that first post I joked about it... Feb 1st.

    UPDATE: $15 now, thanks for the donations from everyone... I really appreciate it. :)
     
    Gophn, Feb 6, 2009
    #13