DongBeetle
New Member
Hi all
I have this project that calls for a power mosfet, so I've bought 4 new IRF530's, and just to test one out I made this little setup, using a 12V 200mA DC adaptor.
![powermosfet2.jpg powermosfet2.jpg](https://www.electro-tech-online.com/data/attachments/41/41783-a22885b278c5cf444af1d8becbc93e02.jpg)
but after about 1 sec the motor starts spinning even thou the gate is not connected?!?
It works fine if I replace the 530 with a NPN transistor, or even with a IRF830 I've salvaged a while ago.
Can anyone tell me why the mosfet behave this way?
Regards.
I have this project that calls for a power mosfet, so I've bought 4 new IRF530's, and just to test one out I made this little setup, using a 12V 200mA DC adaptor.
![powermosfet2.jpg powermosfet2.jpg](https://www.electro-tech-online.com/data/attachments/41/41783-a22885b278c5cf444af1d8becbc93e02.jpg)
but after about 1 sec the motor starts spinning even thou the gate is not connected?!?
It works fine if I replace the 530 with a NPN transistor, or even with a IRF830 I've salvaged a while ago.
Can anyone tell me why the mosfet behave this way?
Regards.