IMPROVED MATCHING TECHNIQUES FOR WIDE-BANDGAP POWER TRANSISTORS

摘要

Some embodiments of the present invention provided an impedance-transforming arrangement comprising a plurality of microwave power transistors 41, and at least one intermediate impedance-transforming or matching device 30. The matching device comprises a plurality of elongate microwave transmission lines 31 provided in or on at least one dielectric substrate 32, extending across or through the dielectric substrate. The microwave transmission lines are coupled at one end to the gate pads 47 of the transistor and at the input ends to a signal input terminal for the transmission line. The transmission lines are substantially directly coupled to one another by means of resistive elements 35 providing a current flow path between the two transmission lines in order to reduce any residual tendency to instability caused by manufacturing variations or misalignment in the assembly process.

主权项

1. An impedance-transforming arrangement comprising a microwave power transistor and at least one intermediate impedance-transforming device, the device comprising:
a plurality of elongate microwave transmission lines provided in or on at least one dielectric substrate, each transmission line having a length and extending at least partially across or through the at least one dielectric substrate, the microwave transmission lines each having:
a first end coupled to the microwave power transistor; anda second end providing a signal input terminal for the transmission line, the transmission lines having a predetermined series inductance per unit length and, in combination with one or more electrically isolated conductive plates or layers, a predetermined shunt capacitance per unit length, such that each length of microwave transmission line together with the one or more conductive plates or layers has a predetermined characteristic impedance and phase constant, wherein at least first and second transmission lines of the plurality of transmission lines are substantially directly coupled to one another by means of at least one resistive element, the resistive element providing a current flow path between the two transmission lines.