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Nick Alexeev
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I'm a big beginner in electricity :-D I just discovered the "Circuit wizard" tool and I'm drawing a circuit with a "MOSFET n channel" transistor. As I understand, when there is voltage on the gate, the transistor is "open" and the current can flow "through" it. So I did the following schema:

Switched open

Behind the tooltip, there is a switch, open. Thus, I expected 0V on the wire between the gate and the switch... And I expected that if the switch was closed, the voltage would be 5V.

Only the second assumption is correct. Indeed, I really don't understand why there is 3.33V on the gate of my transistor. As the switch is open, the wire is like... not connected to anything so where does this voltage come from ?

The answer is surely obvious but I don't know what to look for on the internet to find it :p

Thanks a lot for your answers

I'm a big beginner in electricity :-D I just discovered the "Circuit wizard" tool and I'm drawing a circuit with a "MOSFET n channel" transistor. As I understand, when there is voltage on the gate, the transistor is "open" and the current can flow "through" it. So I did the following schema:

Switched open

Behind the tooltip, there is a switch, open. Thus, I expected 0V on the wire between the gate and the switch... And I expected that if the switch was closed, the voltage would be 5V.

Only the second assumption is correct. Indeed, I really don't understand why there is 3.33V on the gate of my transistor. As the switch is open, the wire is like... not connected to anything so where does this voltage come from ?

The answer is surely obvious but I don't know what to look for on the internet to find it :p

Thanks a lot for your answers

I'm a big beginner in electricity :-D I just discovered the "Circuit wizard" tool and I'm drawing a circuit with a "MOSFET n channel" transistor. As I understand, when there is voltage on the gate, the transistor is "open" and the current can flow "through" it. So I did the following schema:

Switched open

Behind the tooltip, there is a switch, open. Thus, I expected 0V on the wire between the gate and the switch... And I expected that if the switch was closed, the voltage would be 5V.

Only the second assumption is correct. Indeed, I really don't understand why there is 3.33V on the gate of my transistor. As the switch is open, the wire is like... not connected to anything so where does this voltage come from ?

The answer is surely obvious but I don't know what to look for on the internet to find it :p

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ssougnez
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Why is there voltage out of the gate of my transitor

I'm a big beginner in electricity :-D I just discovered the "Circuit wizard" tool and I'm drawing a circuit with a "MOSFET n channel" transistor. As I understand, when there is voltage on the gate, the transistor is "open" and the current can flow "through" it. So I did the following schema:

Switched open

Behind the tooltip, there is a switch, open. Thus, I expected 0V on the wire between the gate and the switch... And I expected that if the switch was closed, the voltage would be 5V.

Only the second assumption is correct. Indeed, I really don't understand why there is 3.33V on the gate of my transistor. As the switch is open, the wire is like... not connected to anything so where does this voltage come from ?

The answer is surely obvious but I don't know what to look for on the internet to find it :p

Thanks a lot for your answers