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Introduction   Having used JFETs (type BF256B) in some of my test circuits whilst experimenting with MOSFETs, I thought it might be interesting to look at the transfer function and see if I could recreate the curve you sometimes see on a datasheet which relates the gate voltage to the drain current.   If you're not used to JFETs (Junction Field-Effect Transistors), they're similar to MOSFETs but the insulation between the gate and the channel is provided not by an actual insula ...
Introduction   More experimenting with MOSFETs. This time I'm going to have a look at the output characteristics.   On a datasheet, output characteristics are usually drawn something like the following two graphs. The first is for the IRF730 part that I have been experimenting with extensively in this series of blogs and the second is for a small-signal part, a BS170:   Curves of drain current against drain-source voltage are drawn for a set of fixed Vgs voltages. The Vgs ...