Power amplifier with distributed capacitor
AssigneeMediatek Inc.
InventorsJin Wook Cho, Hongxi Xue
Life of this patent
Estimating the term…
Abstract
A power amplifier integrated circuit includes a plurality of heterojunction bipolar transistors having a plurality of bases, a plurality of ballast resistors, and a capacitor. Each ballast resistor is connected between a base of the transistor and a DC node to which a DC voltage is applied. The capacitor is connected between an RF node, which supplies an RF signal, and the plurality of bases of the transistors. The capacitor provides a distinct path for the RF input signal having a substantially high capacitance, so that the RF input signal does not suffer significant signal loss.
Claims7
A power amplifier integrated circuit comprising:
- a plurality of transistors each comprising a base;
- a plurality of ballast resistors corresponding to the plurality of transistors, each ballast resistor having a first terminal and a second terminal, the first terminal connected to the base of the corresponding transistor;
- a DC node to which the second terminals of the plurality of ballast resistors are connected;
- an RF node for supplying an RF input signal;
- and
- a capacitor having a third terminal and a fourth terminal, the third terminal connected to the RF node and the fourth terminal directly connected to the plurality of bases.
Dependencies are inferred from the claim text.