Should I Use Absolute Values in JFET Calculation?

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In JFET calculations, the equation Id = Idss(1 - (Ugs/Up))^2 is used to determine the drain current. The question arises whether to use absolute values for Ugs and Up. It is clarified that while absolute values are necessary for p-channel JFETs, they may not be required for n-channel JFETs. The discussion emphasizes the importance of understanding the context of the voltages involved. Proper application of these values is crucial for accurate calculations in JFET analysis.
Monsu
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HI,
When doing some calculations for a JFET (n-channel), I guess u all know this equation:

Id = Idss( 1 - (Ugs/Up))^2

my question is, am i supposed to take the absolute values (modulus) of Ugs and Up?

Id = drain current
Idss = saturated drain-source current
Ugs = gate-source voltage
Up = pinch off voltage.


pls, kinda an urgency!
thanks! :smile:
 
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u cam take the modulas in case of p-jfet
 

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