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Hi all!

I've got a little problem with my nearly finished mousefan. The fan don't have enough power to start spinning on it's own. Now this is a 5V fan and it's soldered directly to the 5V input on the board with a switch in between. I checked the soldering points with a multimeter before connecting them and it was 4.92V which got the fan to spin perfectly. But when I measure it afterards with all the soldering done it is 4.74V and this is too little juice. How come the current has changed? The only difference from before is the switch, but in my opinion that shouldn't matter since it's only re-routing the power, right?

I'm kind of bummed now since I've done pretty much modding with the casing that consists of 3 pieces (Apple Pro mouse) and only had to put some holes on the top for airflow to complete it.

So, anyone have an idea what is causing the drop in current and what can be done to solve it?

I would suggest that you are using a data-line to power to mouse. If you use a regular multimeter, it will indicate near 5 volts as the line changes rapidly between 0 and 5 volts and the meter is too slow to follow. If this is the case, just find another point to take power from.

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Metku | AlltheMods | LedCalc | Teknolelu | AndroidCoding
Main Computer: Intel i5, MSI H55M-ED55, 12 Gigabytes of DDR3, 3 Terabytes of HDD, GTX295 and Benq 27"

Hi Japala!

By a regular multimeter do you mean an analog? I'm using a digital multimeter and I find it very responsive.
I took another look at the points where the cable goes in and I'm pretty positive I got the right ones

The colors of cables are from left to right:
Red/Black, Grey/Black, Green/Black, Black (thin), Black (thick)

I took the + from the Red/Black which now measures 4.77V and used the thin Black as -
(This is the highest value I can get from trying all of them, seems logical considering the colors also)

And I don't think I'm able to get the juice from another point on the board since the first thing the power passes through is a resistor.

Anyways I did Measure the points again and it made me really confused..
When I started this project I checked the Red/Black and it was 4.92V and I also tried
sticking the fan directly to those 2 points just to be sure, and as I said before it spun perfectly.
May I have damaged something in the process causing the small drop in current?

Getting the power from another location seems out of the question now, huh?

Seems like you have the right pins. People often trace then pins and take the power from the pins of the logic chip. This makes it easy to use a data pin by mistake.

Digital/analog, doesn't matter. Logic signals change state so fast that even a digital multimeter is not enough to react. Oscilloscope is right tool then.

It is bit odd that the fan doesn't work with the mouse. Did you initially test the fan with or without the mouse? If you tested it without the mouse, the USB might have given you the max. 500mA to play with. The mouse might tell the USB controller that it only needs x mA to work with and the controller limits the amount of current it passes to the device... hard to be sure...

_________________
Metku | AlltheMods | LedCalc | Teknolelu | AndroidCoding
Main Computer: Intel i5, MSI H55M-ED55, 12 Gigabytes of DDR3, 3 Terabytes of HDD, GTX295 and Benq 27"