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    Using a 9V and 12V USB Voltage Converter on my P750DM2-G USB 3.0 Ports

    Discussion in 'Sager and Clevo' started by rwx, Aug 26, 2019.

  1. rwx

    rwx Notebook Enthusiast

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    Hey all

    So I was wondering if any of you know what's the maximum current my laptop's USB 3.0 ports support? As far as I am aware the maximum current of a USB 3.0 port is a 900ma but I believe some vendors can do more. Are there any specs for this laptop that can tell me this?

    I know that if I use a USB voltage converter the maximum current the USB port supports will drop significantly and I don't want to damage my port which leads me to my next question: Do these laptops' USB ports have an over-current safety?
     
    rwx, Aug 26, 2019
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  2. Meaker@Sager

    Meaker@Sager Company Representative

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    I would not exceed the usb 3 spec on the ports.
     
    Meaker@Sager, Aug 26, 2019
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  3. poprostujakub

    poprostujakub Notebook Consultant

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    USB ports in this model are powered via 2-amps UP7549 power switches. Theoretically these ICs have any possible protection systems, but from my experience, they will fail when you will try to connect anything which isn't standard USB device.
    This is particularly true, if we talk about cheap chinese boost converters, because they inject enormous amounts of interferences, voltage spikes and current surges into power supply.
     
    poprostujakub, Aug 26, 2019
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  4. Meaker@Sager

    Meaker@Sager Company Representative

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    Plus you need to account for losses in the conversion.
     
    Meaker@Sager, Aug 26, 2019
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  5. rwx

    rwx Notebook Enthusiast

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    Thx for that, I will only use a 5V one - no conversion at all.
     
    rwx, Aug 26, 2019
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  6. Meaker@Sager

    Meaker@Sager Company Representative

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    What are you driving?
     
    Meaker@Sager, Aug 26, 2019
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  7. rwx

    rwx Notebook Enthusiast

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    I want to connect a router. The router is rated at 12V 1.5A - a bit too much for a USB port and the product I purchased is a USB step up converter rated at 12V 1A and the description of the converter has a warning "the USB port must support 2.1A or greater".

    I use a standard 5V right now to power my HDMI switcher rated at 5V 1A and it seems to work fine.
     
    Last edited: Aug 28, 2019
    rwx, Aug 27, 2019
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  8. Meaker@Sager

    Meaker@Sager Company Representative

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    12v 1a = 12 watts

    That's a lot for a USB port.
     
    Meaker@Sager, Aug 27, 2019
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