Please be gentle as I am a total newbie with electronics.
I recently bought an Arduino beginners kit. In that kit was a 9V motor with the proper transistor (I think these are also called MOSFET?). The printing on the transistor reads IRF520N IOR P533B D5A2
(see picture left). I have started my own little project and bought a 12V pump and hooked it up just as I previously did with the motor from the kit and it worked perfectly (see picture). Since then I decided I wanted to buy more transistors of the same type and I found one which I thought was the same. It is labeled IRF520N IOR P702D AP9Q
(see picture right) but when I use that transistor the pump doesn't start pumping.
Apparently the two transistors are not completely identical. I found the datasheet to the newly acquired transistor (listed on the page of the online store I bought it from) but I don't really understand anything it's trying to tell me. Also I couldn't find the datasheet for the one delivered with the Arduino.
So my questions are:
- Why is that transistor not working?
- Could you point out which values in the datasheet are important to me so I can pay attention to those when I look for another transistor?
- What does the transistor actually do which I bought and can I still use it for something (I actually bought quite a lot of them..)?
If I missed any important information please ask in the comments and I will include it in my post. I included a schematic at the bottom.
Edit #1:
As joren vaes suggested I used the new transistors with the old motor and a 9V power supply. To my surprise that actually made the motor spin. So it looks like the new transistor can't handle the 12V?
Edit #2:
I did some experimentation with pump, 9V and older/newer transistor.
Using the 9V batterie with the 12V pump works fine but only with the old transistor. With the new transistor the pump moves super slow and the transistor got worryingly hot. The old transistor doesn't heat up noticeably. As suggested by joren vaes i made another photo of the setup which shows the wiring properly and photos (first page, second page) of the instructions which came along in the kit. There isn't really any more valuable information about the transistors which came along if you were hoping for that.
Also the Arduino supplies 5V and the code I uploaded just sets the transistor pin HIGH
when the button is pressed. I know that I wouldn't need an Arduino for that ;)
Edit 3: Included schematic. I hope I didn't do anything wrong..
simulate this circuit – Schematic created using CircuitLab