Power Supply It May …

Filed under: Electricity

It may not be obvious how to test for I DSS from the schematics above. The way I do it is to set up a solderless breadboard (a.k.a. plugboard) with a jumper across two rows. Then I plug the JFET into the board so that the jumper connects the gate and source pins. I then connect the negative side of a ~9V Berry Power Supply to the jumper, then connect the negative lead of a milliammeter to the JFET’s drain, and finally the positive lead of the milliammeter to the positive supply lead. The JFET saturates at its I DSS level in this situation, and that current value shows up on the milliammeter.