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[Solved] Powering camera using USB power

Forum Digital Camera : General Discussion [Solved] Powering camera using USB power

I want to power my camera using USB power.

The camera is a Canon S95 and takes 3.7V (1000mAh) batteries which read an output voltage of about 4.1 when charged.

I want to keep the camera on for a long period of time so is it safe for me to use a few resistors (which I did) and decrease the USB output voltage to 4.1 and power the camera that way?

Will this cause damage to the camera?

Do milliamps also play some role in this that I haven't yet considered?

Message edited by Skedgy Sky on 03-24-2011 at 03:23:45 AM

Reply to Skedgy Sky

USB 2.0 has usually 500mA which might be adequate for the camera. Worth trying.

Reply to Ubrales

I tried that but nothing happened.

Message quoted 1 times

Reply to Skedgy Sky

Skedgy Sky wrote :

I tried that but nothing happened.

That means that the camera needs more power than the USB can deliver. Similar to external HDDs connected to USB without the power adapter connected.

Reply to Ubrales

I kind of already figured that.

I'm just wondering if powering a camera using an external power source means that a certain amperage is needed and if using more than the amperage of the batteries would cause damage to the camera.

Message quoted 1 times

Reply to Skedgy Sky

Skedgy Sky wrote :

When you know it is not working, stop! Clearly, more amps are required than the USB port can supply. Why find out whether damage could happen?

Reply to Ubrales

Well I don't really want to know if it'll get damaged; I don't want to damage it.

I'm trying to find out how many amps the power source needs to be able to power the camera (since I want the camera on for long periods of time).

If the batteries for this camera have a capacity of around 1000mAh (and output around 4v), does that mean I need a power supply that outputs around 4 volts at 1 amps? Does amperage work the same way for batteries as it does for regular dc power supplies?

Reply to Skedgy Sky

Best answer

Capacity is in Amp-hours. 100 Amp-hours could be 1 Amp for 100 hours OR 100 Amps for 1 hour (not a linear relationship).

Somewhere on your camera or in the manual, the Watts may be stated. This is a better indication for the Amp draw. In DC circuits, Watts = Amps X Voltage. From this you can do the calculations.

Reply to Ubrales