How to connect the MOSFET driver with the N-MOSFET

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JackJTR

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Above attach is the circuitry i design to try out the MOSFET Driver(TC427CPA) with the N-MOSFET(FDC6561AN). The R1 resistor are used to pull the pin 22 down while R2 is the current limiting resistor for the LED. My goal is just to used the arduino 5V to turn the N-MOSFET fully on (RdsOn = 10V). I know i can just used the IRF520N, but i am just really curious and wanted to understand the mosfet driver more. So after some researching, i decide to try and design a mosfet circuit using the mosfet driver and above are the product form the circuit designing, So i am wondering will teh above circuit work?
 
It should work OK.

The only change I'd suggest is adding a low value resistor between the driver and FET gate. That's normal, to limit the peak current to within the driver safe value as the gate capacitance charges or discharges.

The TC427 is rated at 1.5A output; to limit to that with a 12V supply, a resistor around eight ohms would be ideal.
(And be sure the driver has good decoupling on its power supply, and a good ground between it and the FET source).
 
Could you elaborate briefly on how you calculate the resistor? A pretty low value BTW.
 
Could you elaborate briefly on how you calculate the resistor? A pretty low value BTW.
Ohms Law!

12V (the supply in use) / 1.5A (the rated output current of the FET driver device) = 8 Ohms.

That's the minimum "guaranteed safe" value to stay within the data sheet ratings. Lower may be possible if you know the frequency and duty cycle and can predict the device dissipation, keeping that reasonable - but I'd stick with the basic safe value.

Higher values are fine, as long as you do not need the FET to switch as fast as possible. Slow switching will increase the FET power loss; probably irrelevant if just switching such as a relay, but a bad idea for PWM type applications were losses and speed are critical.
 
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