The circuit following uses the outputdigital of microprocessor (0V or 5V) to drive a relay or motor.both the transistors work in regime ofcommutation (ON /OFF) and the circuit can be fed with any tension between 6Vand 18 V.
Could someone please help me understand how this circuits works?
In general terms i suppose this should be something like ,due to the fact that the npn transistor switch between cutting and saturation due to voltage from the microprocessor, the FET is on or off triggering the relay and motor, or not depending on its state.
2)considering hFE = 240 VBE = 0.7V, VCEsat= 0.4V, determine the intensity of current that the output of microprocessor has of provide to the circuit work correctly.
For this
\(
Voutput+R//R*Iouput+VBE=0V
5V+(1*10^3)//100*10^3*Ioutput+0.7=0
Ioutput=4,34 m A
\)
Is this correct?
3)Determine a value minimum possible to the tension of threshold VT of
MOSFET channel N.Justify.
I have no idea how to do this.What should i start to determine this?
Thanks
Could someone please help me understand how this circuits works?
In general terms i suppose this should be something like ,due to the fact that the npn transistor switch between cutting and saturation due to voltage from the microprocessor, the FET is on or off triggering the relay and motor, or not depending on its state.
2)considering hFE = 240 VBE = 0.7V, VCEsat= 0.4V, determine the intensity of current that the output of microprocessor has of provide to the circuit work correctly.
For this
\(
Voutput+R//R*Iouput+VBE=0V
5V+(1*10^3)//100*10^3*Ioutput+0.7=0
Ioutput=4,34 m A
\)
Is this correct?
3)Determine a value minimum possible to the tension of threshold VT of
MOSFET channel N.Justify.
I have no idea how to do this.What should i start to determine this?
Thanks
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