Here is how to test a mosfet: https://forum.digikey.com/t/how-to-test-a-mosfet/1985?utm_adgroup=General&utm_source=google&utm_medium=cpc&utm_campaign=Dynamic Search_RLSA_Cart&utm_term=&utm_content=General&gclid=EAIaIQobChMImImSyKrF5wIViLzACh0arwWHEAAYASAAEgIXdfD_BwEHi
I would like to know how to check a 8 pin Mosfet with a multimeter i'm trying to fix my 9gram servo it doesn't rotate when power is applied to it i check the motor i have continuity.
Its a TowerPro servo, the number on the Mosfet is 117L912 and by connecting a lipo battery is how the power is applied,Can't do much with just vague details!
Mosfet part?
Servo?
How is power applied?
RC servo?
Schematic?
Etc etc?
Max.
Thanks here is the picture for my servo...Here is how to test a mosfet: https://forum.digikey.com/t/how-to-test-a-mosfet/1985?utm_adgroup=General&utm_source=google&utm_medium=cpc&utm_campaign=Dynamic Search_RLSA_Cart&utm_term=&utm_content=General&gclid=EAIaIQobChMImImSyKrF5wIViLzACh0arwWHEAAYASAAEgIXdfD_BwE
Note, it refers only to 3 pins. Many small mosfets (including yours) will have multiple pins connected together of the Drain, multiople pins connected together for the Source, and one for the Gate. An example:
View attachment 198710
Since you have 8 pins, one MIGHT assume 4 on one side were the drain and 3 on the other were source. You only need to test one pin for each connection, e.g., 1 pin for drain. To be safe, you need the part number for your mosfet to determine its true pinout.
On the source side on the second pin after the dot i got 0.499 with the multimeter on diode mode, on the third pin i got 3.309 on the Gate pin i got 3.496Here is how to test a mosfet: https://forum.digikey.com/t/how-to-test-a-mosfet/1985?utm_adgroup=General&utm_source=google&utm_medium=cpc&utm_campaign=Dynamic Search_RLSA_Cart&utm_term=&utm_content=General&gclid=EAIaIQobChMImImSyKrF5wIViLzACh0arwWHEAAYASAAEgIXdfD_BwE
Note, it refers only to 3 pins. Many small mosfets (including yours) will have multiple pins connected together of the Drain, multiople pins connected together for the Source, and one for the Gate. An example:
View attachment 198710
Since you have 8 pins, one MIGHT assume 4 on one side were the drain and 3 on the other were source. You only need to test one pin for each connection, e.g., 1 pin for drain. To be safe, you need the part number for your mosfet to determine its true pinout.
Not necessarily. The servo tester could be bad. Did you run a control?... i use a servo tester and when i use a servo tester it doesn't move, so therefore it's a bad servo.
Did you bother reading posts #3 and #7? It was YOU in your first post that called it a mosfet. I simply pointed out they can and often do have more the 3 pins.I'm not a electronics technician but i'm trying to fix it, there is a SMD Transistor on the board next to the motor and what i know is all Transistors have 3 legs some people call them Mosfet their not Mosfet, Mosfets
has 6 legs, 8 legs but you also have some dual Transistors with 6 legs and here is where it doesn't make sense to me.