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Wrong simulation for VP0808 mosfet?

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clros

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In this simulation (I am using multisim 14.0), the output voltage value (measured from XMM1) multimeter is:

~0V when S1 is on VDD
~0V when S1 is on GND
3.3V when S1 is on VSS

Annotazione 2019-12-08 215310.png

But, if I make this circuit on Breadboard whit a real VP0808, it do not faithful to simulation (I have 3.3V when S1 is on GND).

Is it a simulator error?
 

Do you understand the meaning of Vgs(th) specification in datasheet, particularly the wide threshold voltage range?
 

Do you understand the meaning of Vgs(th) specification in datasheet, particularly the wide threshold voltage range?
If I understand well, for P-MOSFET, the Vgs should be less than Vth:

Vgs < Vth

When I connect my gate to Vdd I have Vgs = 0V
When I connect the gate to GND, Vgs = -3.3V
When I connect the gate to Vss, Vgs = -6.6V

It is correct?

In this case, my Spice model have than VTO = -3.55V. If I connect gate to GND, the Vgs < Vth is false and I have 0V to drain pin.
 

Can anyone help me, please?
 

I thought you already answered the question yourself. You have explained the simulation result, the real MOSFET has apparently much lower threshold voltage, well possible according to the datasheet.
 

I thought you already answered the question yourself. You have explained the simulation result, the real MOSFET has apparently much lower threshold voltage, well possible according to the datasheet.

Yes, OK.
I would like to get a behavior like the one described by the simulator, in particular that the mosfet does NOT lead when Vgs is equal to GND.

So I should choose a MOSFET with a fairly high Vth. Could you suggest such a component?
 

Max. Vgs,th of 4.5V of VP0808 is relative high, you probably won't find any devices with Vgs,th,min > 3.3V.
 

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