FLEXIBILITY

In practical circuits, an n-channel JFET sometimes can be replaced with an n-channel MOSFET; p-channel devices similarly can be interchanged. However, the characteristic curves for MOSFETs are not the same as those for JFETs. The source-gate (S-G) junction in a MOSFET is not a p-n junction. Forward breakover does not occur under any circumstances. If this junction

Fig. 1. A family of characteristic curves for a hypothetical n-channel MOSFET.

conducts, it is because the S-G voltage is so great that arcing takes place, damaging the MOSFET permanently. A family of characteristic curves for a hypothetical n-channel MOSFET is shown in Fig. 1

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