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Can a microcontroller drive a MOSFET with an optocoupler?
Anything up to about 10 kHz should work OK./ For faster PWM a properly designed driver is required. As far as the MOSFET is concerned, an optocoupler is just a transistor. As far as the microcontroller is concerned, an optocoupler is just an LED.
How does an optocoupler limit the gate voltage?
You can limit the gate voltage by having a resistor in series with the optocoupler’s transistor. If the transistor to ground is 4k7 you can pick 10k for this. If the optocoupler’s LED is on the transistor will conduct and make the gate high, switching the MOSFET on.
Do you need a transistor to drive a MOSFET?
So, all you need is a normal transistor-driven MOSFET circuit, and a normal microcontroller-driven LED circuit. Here’s an example of driving a MOSFET with a transistor: So Q2 is the output side of the opto-couper. R2 would be replaced by the input LED side of the opto-coupler and it’s current limiting resistor.
Which is the output side of the optocoupler?
So Q2 is the output side of the opto-couper. R2 would be replaced by the input LED side of the opto-coupler and it’s current limiting resistor. The optocoupler’s isolation gives you the advantage that you can place its output transistor anywhere you like, independent of the microcontroller’s supply voltage.
What kind of optocoupler is the fod3180?
The FOD3180 is a high-speed MOSFET gate drive optocoupler with 2A output current. It consists of an aluminum gallium arsenide (AlGaAs) light-emitting diode (LED) optically coupled to a CMOS detector with PMOS and NMOS output power transistors integrated circuit power stage.
Can a MOSFET be pulled to a 12V level?
It allows me to pull the gate of the MOSFET to the 12V level using just 3.3V. The below schematic I devised for the combination with a PCF8574 port expander. Its pins should default to output, high. In high state it can source only 0.3 mA or so, very little, enough to drive a transistor but not an LED.
What is the function of the fod3180 optocoupler?
FOD3180 is a MOSFET Gate Driver Optocoupler introduced by Fairchild Semiconductors basically used for the isolation of two circuits. It is a MOSFET Optocoupler which has three parts i.e.a AlGaAs Infrared emitting diode, output power transistors, and a CMOS detector which functions by sensing the infrared light.
Can a optocoupler be used to drive an Arduino?
It however can sink at least 20 mA, so that’s good enough to drive an LED, or an optocoupler. The idea behind this schematic: when switched on, the ports are high, no current through the LED, MOSFET gate pulled low, and it’s off.