A MOSFET acts as a switch. On and Off.
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The first circuit:
We have a DC source of 10V connected to the Source (S) of the N-Channel MOSFET. There is a square wave modulated signal connected the the Gate (G) of the MOSFET, which when provided the correct amount of Voltage (V), allows the Source (S) current to flow into the Drain (D).
The Drain (D) is connected to a 300ohm resistor that limits current getting to the LED (Light Emitting Diode), which is then connected to ground to continue the circuit cycle.
The amount of voltage applied to the Gate allows a certain amount of current to from Source to Drain.
N-Channel: Needs Positive (+) voltage to activate the gate. (Image: Arrow pointing away from the gate).
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The second circuit:
DC source - connected to Source of P-Channel MOSFET
- DC square wave modulated signal connected to MOSFET Gate (G)
- Negative voltage (or 0) turns on Gate, Which allows source to flow to Drain (D).
P-Channel: Requires Negative voltage on the Gate (G). (Image: Arrow points toward gate)
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Third circuit: The 2 circuits combined with each other.
