IDSS (referred to as the drain current for zero bias) is the maximum current that flows through a FET transistor, which is when the gate voltage, VG, supplied to the FET is 0V. IDSS is the drain current for zero bias, when the gate voltage is (zero) 0V given a certain Vds, and refers to a depletion mode FET (The device would be On with. IDSS can mean: Institute for Defence and Strategic Studies · Intelligent decision support systems · Integrated Development Support System · Integrated Decision. In a JFET, IDSS is known as ______ a) drain to source current b) drain to source current with gate shorted c) drain to source current with gate open d) none of. IDSS is drain to drain to source saturation current.