Transistor question

aab1

Pedelecer
Jun 20, 2007
42
0
Controllers with pedal assist seem to be unexistant worldwide from what I could find.

I found an IRF540, but how do I know if the pins are in different places than the original one?

Thanks
 

flecc

Member
Oct 25, 2006
53,128
30,555
The following link shows the pinouts for the IRF540, and there's a data sheet for you to download.

RS Components

I can't find any data on the NEC MOSFET you have installed at present though, so not sure if that helps.
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Ian

Esteemed Pedelecer
Apr 1, 2007
1,333
0
Leicester LE4, UK.
To determine the connections on the existing MOSFET trace the wiring through the tracks on the printed circuit.

One wire from the battery should go (Possibly via a switch and/or fuse) to one pin on the MOSFET. If that wire is negative then the pin is the SOURCE, or if the wire is positive then the pin is the DRAIN.

Another MOSFET pin will go to one of the motor terminals, if it connects to the positve motor terminal then the pin is the SOURCE, otherwise it is the DRAIN.

The third pin is the GATE, this will not be connected directly to the motor or battery but will be connected to one or more other components.
 

aab1

Pedelecer
Jun 20, 2007
42
0
Thanks for letting me know how to identify the pins, I know which is which now but I can't access the link you posted for the pin outs of the IRF540, it says session timed out.
 

Ian

Esteemed Pedelecer
Apr 1, 2007
1,333
0
Leicester LE4, UK.
To get the IRF540 data sheet, go here, enter IRF540 into the product search box then click on the pdf symbol by the IRF540 which most closely matches what is available to you, finally select data sheet in the pop up.
 

flecc

Member
Oct 25, 2006
53,128
30,555
I can't access the link you posted for the pin outs of the IRF540, it says session timed out.
Apologies for that aab1, I didn't realise they used timeout protection on their search function.
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