JFET Inverter

[JeanTech]

Hi there

I'm currently stuck on a simple JFET inverter design. I know the BJT equivalent, but am unsure how to do the equivalent using a JFET. How would I go about designing an inverter using an N-channel JFET? I'm assuming no gate resistor is necessary, since the JFET has a high impedance and only acts on voltage.

I was thinking of inserting a resistor between Vcc and drain to drop the voltage to 0 V when the JFET is active to achieve the inversion function. How would I calculate this resistor value? At the moment my circuit is acting more like a switch than an inverter.

Attached, please find my preliminary design.

Thanks in advance
Jean

 

[alec_t]

Hint:
To turn an N-channel JFET off you need to make the gate negative with respect to the source.