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    Where can I find a 12V suppy in my notebook?

    Discussion in 'Hardware Components and Aftermarket Upgrades' started by moral hazard, Sep 18, 2009.

  1. moral hazard

    moral hazard Notebook Nobel Laureate

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    Hi,

    I'm looking for somewhere inside my notebook that I could tap off 12V from.

    My notebook is a toshiba tecra a9.

    I only need a 12V 0.08A supply.
    Any suggestions?
     
    moral hazard, Sep 18, 2009
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  2. K-TRON

    K-TRON Hi, I'm Jimmy Diesel ^_^

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    You can try looking by the DC input jack, or from the screen inverter.

    Most likely they will be higher than 12V, so you will need to build a small circuit which can drop the voltage down to your desired 12V.
    Or
    You can rectify the 5V power from your USB port to 12V

    K-TRON
     
    K-TRON, Sep 18, 2009
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  3. moral hazard

    moral hazard Notebook Nobel Laureate

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    thanks K-TRON.

    I don't really want the power from the inverter because it would be hard to get the wires installed properly so that I can move the screen.


    That's actually a good idea about looking near the power jack.
    My AC adapter supplies 15V, which is close.
    I'll have to look around that area a bit.

    I'm guessing it wouldn't cause any damage if I take 12 V from a USB port, would it?
    I only need a very low current.

    Again, thanks for the suggestions.
    I will think a little bit.

    Any more suggestions welcome :)
     
    moral hazard, Sep 18, 2009
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  4. K-TRON

    K-TRON Hi, I'm Jimmy Diesel ^_^

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    Well rectifying voltage is pretty efficient. So if its only 0.08amps at 12V, which I presume is that fan, it would take about 0.2 amps from the USB hub at 5V. This would still be under the USB limit on current draw.

    Make a small circuit, or have some friends who are wizards at electrical work do it for you. After the circuit is tested and working, just cover it up in hot glue, or electrical tape and mount it in your laptop. It shouldnt take up much space at all.

    K-TRON
     
    K-TRON, Sep 18, 2009
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  5. moral hazard

    moral hazard Notebook Nobel Laureate

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    yes, a fan. A very thin fan that is perfect, just needs 12V.
    And a simmilar 5V fan will cost me $40 AUD so I'm going to use this one instead.

    good to know :)

    Looks like that is really the best option.
     
    moral hazard, Sep 18, 2009
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  6. ViciousXUSMC

    ViciousXUSMC Master Viking NBR Reviewer

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    Battery Terminals, I think most laptop use a 12v battery?
     
    ViciousXUSMC, Sep 18, 2009
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  7. moral hazard

    moral hazard Notebook Nobel Laureate

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    I think my battery is 10.8V.

    But for a 12V fan that should do.
    I might actually try that and see how fast it spins.
     
    moral hazard, Sep 18, 2009
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  8. Tinselworm

    Tinselworm Notebook Deity

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    *BOOM* Bwahahhahahhaa...



    *FIZZES* IT'S ALIVE!!! IT'S ALIVE!!!!!


    you'll get better luck looking for a 5V supply in a notebook.
     
    Tinselworm, Sep 18, 2009
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  9. moral hazard

    moral hazard Notebook Nobel Laureate

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    OMG, I just realized where I have seem bill bailey before.
    I have seen his standup before.

    I don't suppose you really are him? :D lol.


    EDIT: I can't find the pinout of my battery.

    I have to test with a DMM now, if anyone has a datasheet for any toshiba battery I would like to see it.
     
    moral hazard, Sep 18, 2009
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  10. K-TRON

    K-TRON Hi, I'm Jimmy Diesel ^_^

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    Actually you need to be careful with this.
    For example, my battery in my E1505 is 11.1V DC
    But the terminals which charge it output close to 14V
    measure the current output of the charging jack with a meter and see what it outputs

    You can always run the fan less than 12V, but as a general statement, you do not want over 12V, as you will burn the fan out.

    K-TRON
     
    K-TRON, Sep 18, 2009
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  11. ViciousXUSMC

    ViciousXUSMC Master Viking NBR Reviewer

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    Viva La Resistor :D
     
    ViciousXUSMC, Sep 18, 2009
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  12. moral hazard

    moral hazard Notebook Nobel Laureate

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    I cant find any info on which pins to use.
    There are way to many of them on the battery.

    I'm going to do some tests with a DMM today, but if anyone knows which ones are likely to be what I'm looking for please let me know :)
     
    moral hazard, Sep 18, 2009
    #12