Wideband FET voltage amplifier circuit - has voltage offset unit and additional transistor as load resistance connected to output of amplifier

摘要

The wide-band, f.e.t. voltage amplifier has a load resistance connected behind or after the amplifier transistor. The load resistance allows the drain current tolerance to have no effect on the d.c. working point of the stages connected to the amplifier's output. A current source(T2) with high source resistance pref. a voltage offset unit, and an additional transistor(T3) as the load resistance, are connected to the output of the amplifier transistor(T1). The voltage offset is designed as series-connected diodes(D1-D4) and a transistor(T4) connected after or behind the diodes. The centre tap between the diodes(D1-D4) and the transistor(T4) is connected to the gate of the extra transistor(T3).