is an io input output transistor and may function as an output stage amplifier io transistors are well known in the relevant arts and are characterized by their relatively high breakdown voltage and large geometries transistor 201 operates between output port 270 and output ground 271 output port 270 may provide load not shown and bias current and will also typically connect to a matching network not shown for matching load impedance to output impedance dc direct current bias circuit 230 provides offset bias for the gate of transistor 201 in certain embodiments transistor 201 operates as an amplifier in the triode region as a class a amplifier coupling capacitor 225 couples a rf signal into the output stage 281 capacitor 225 may be embodied as an on chip capacitor formed by for example well known mos processes only a small capacitor may be required for example at 2 ghz gigahertz a 1 pf picofarad capacitor has a susceptance of approximately 10s siemens leading in driver stage 280 transistor 211 may operate in common gate mode the gate bias for transistor 211 is set by dc bias circuit 231 inductor 220 connects a dc power supply v dd rail to drain of transistor 211 inductor 220 may block rf signals from entering the power supply rail 228 and acts in conjunction with capacitor 225 and inductor 221 to provide inter stage matching for the rf signal inductors 220 and 221 may be implemented as on chip spiral conductors with suitable inductance and q values according to techniques well known in the art transistor 212 may operate in common source mode and.