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PC_USB <--> Digital_Cam, do u think power is drawn frm

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nicleo

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Hopefully someone who has knowledge on digital camera design will help me clarify my doubt as follows:

When transferring files from Digital Camera to PC via USB interface, do you think the digital camera draws power from PC, or from it's battery?
 

pisoiu

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Re: PC_USB <--> Digital_Cam, do u think power is drawn

I do not have very much knowledge about digital camera design, but the maximum current which can be drawn from USB port is 500mA, which I think is not enough for a digital camera. My guess would be that the power is taken from batteries.

/pisoiu
 

nicleo

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I borrowed an Olympus Digital Camera from my cousin. Before it caused problem to my m/board (which is damaged now), my PC always detected it as a removable disk/device, like those handy drives or flash drives or thumb drives. If I'm not mistaken, those handy drives are not self-powered but draw current from the computer via USB. I really wish you guy to help as I want to know the 'mechanism' how the digital camera, when connected to PC via USB, would damage my m/board (or more specifically damage the Intel ICH5 chipset).
 

M!k

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Re: PC_USB <--> Digital_Cam, do u think power is drawn

Sounds strange because on modern boards the current is monitored. If it increases too much the USB port will be powered down, but nothing will be damaged.

Mik
 

hock

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Re: PC_USB <--> Digital_Cam, do u think power is drawn

camera uses battery power for the it self.
just remove the batt pack and try connecting it to usb it will not get detected.
i have tested it on a sony.
hock
 

nicleo

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Re: PC_USB <--> Digital_Cam, do u think power is drawn

M!k said:
Sounds strange because on modern boards the current is monitored. If it increases too much the USB port will be powered down, but nothing will be damaged.
Pls advise what's the protection?
Do you think there are fuses on m/board to protect the USB port (controller) from damaged?
Pls study the details of my problem here ( )
 

M!k

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Re: PC_USB <--> Digital_Cam, do u think power is drawn

the fuses are rather ICs with integrated MOSFETs, for example:
**broken link removed**
**broken link removed**
**broken link removed**
I don't know if your chipset (Intel FW82801EB) has such kind of drivers integrated on the chip, but I doubt about that because of the high currents. So I think these devices are additional present on your board (perhaps you can trace back the Vbus-line ?).
I also know these nice Windows pop-ups if the USB current is exceed. Vbus is then powered down (until a reboot or a certain time - can't remember).


Mik
 

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