Compound transistor circuitry

摘要

A compound transistor circuitry having an output characteristic resembling that of a pentode vacuum tube comprises: a first field effect transistor having a saturated-type output characteristic resembling that of a pentode vacuum tube; and a second field effect transistor having an unsaturated-type output characteristic resembling that of a triode vacuum tube. The first and second field effect transistors have a conducting channel of a single and same conductivity type, respectively. The second field effect transistor is connected in series with the drain current path of the first field effect transistor. This second field effect transistor is rendered conductive only when the drain-source voltage of the first field effect transistor exceeds its pinch-off voltage.