Abstract: Systems and methods for thermal droop compensation in power amplifiers with field effect transistors (FETs) are disclosed. In one aspect, a droop compensation circuit having a heat-sensitive element is embedded in an amplifier in the amplifier chain. The heat-sensitive element tracks changes in temperature for the amplifier and generates a trigger signal for a correction circuit that modifies the amplifier chain to provide thermal droop compensation. Variations contemplate changes to the nature and location of the correction circuit. By compensating for temperature droop in this fashion, rapid pulsing signals that generate rapid pulses of heat may be transmitted across an effectively linear power amplifier chain without having to deal with droop effects. Particular aspects of a FET-based power amplifier may use diodes as a heat-sensitive element.

Abstract: An RF power package includes a substrate having a metallized part and an insulating part, an RF power transistor die embedded in or attached to the substrate, the RF power transistor die having a die input terminal, a die output terminal, an input impedance and an output impedance, a package input terminal formed in the metallized part or attached to the insulating part of the substrate, a package output terminal formed in the metallized part or attached to the insulating part of the substrate, and a first plurality of planar tuning lines formed in the metallized part of the substrate and electrically connecting the die output terminal to the package output terminal. The first plurality of planar tuning lines is shaped so as to transform the output impedance at the die output terminal to a higher target level at the package output terminal.

Abstract: An RF power package includes a substrate having a metallized part and an insulating part, an RF power transistor die embedded in or attached to the substrate, the RF power transistor die having a die input terminal, a die output terminal, an input impedance and an output impedance, a package input terminal formed in the metallized part or attached to the insulating part of the substrate, a package output terminal formed in the metallized part or attached to the insulating part of the substrate, and a first plurality of planar tuning lines formed in the metallized part of the substrate and electrically connecting the die output terminal to the package output terminal. The first plurality of planar tuning lines is shaped so as to transform the output impedance at the die output terminal to a higher target level at the package output terminal.

Abstract: A semiconductor package includes a metal baseplate, a semiconductor die having a reference terminal attached to the baseplate and an RF terminal facing away from the baseplate, and a multilayer circuit board having a first side attached to the baseplate and a second side facing away from the baseplate. The multilayer circuit board includes a plurality of interleaved signal and ground layers. One of the signal layers is at the second side of the multilayer circuit board and electrically connected to the RF terminal of the semiconductor die. One of the ground layers is at the first side of the multilayer circuit board and attached to the metal baseplate. Power distribution structures are formed in the signal layer at the second side of the multilayer circuit board. RF matching structures are formed in a different one of the signal layers than the power distribution structures.

Abstract: A semiconductor package includes a metal baseplate, a semiconductor die having a reference terminal attached to the baseplate and an RF terminal facing away from the baseplate, and a multilayer circuit board having a first side attached to the baseplate and a second side facing away from the baseplate. The multilayer circuit board includes a plurality of interleaved signal and ground layers. One of the signal layers is at the second side of the multilayer circuit board and electrically connected to the RF terminal of the semiconductor die. One of the ground layers is at the first side of the multilayer circuit board and attached to the metal baseplate. Power distribution structures are formed in the signal layer at the second side of the multilayer circuit board. RF matching structures are formed in a different one of the signal layers than the power distribution structures.