Title :
Broadband GaN HEMT push-pull microwave power amplifier
Author :
Jong-Wook Lee ; Webb, K.J.
Author_Institution :
Sch. of Electr. & Comput. Eng., Purdue Univ., West Lafayette, IN, USA
Abstract :
We report a broadband, linear, push-pull amplifier that utilizes GaN-based HEMTs grown on SiC substrates. The high power density capabilities of these devices can be enhanced by the high efficiency achievable with push-pull operation. Good amplifier performance is facilitated by use of a new low-loss balun that is implemented with three symmetric coupled lines and which showed insertion loss of less than 0.5 dB per balun. The bias was injected through the baluns, thereby simplifying the amplifier design and reducing loss associated with dc decoupling capacitors. Using two 1.5 mm HEMTs with 0.35-μm gate length, a push-pull amplifier produced a small-signal gain of 8 dB at 5 GH2, a 3 dB bandwidth of 3.5-10.5 GHz, and a PAE of 25%.
Keywords :
HEMT circuits; III-V semiconductors; baluns; differential amplifiers; gallium compounds; microwave power amplifiers; wide band gap semiconductors; wideband amplifiers; 0.35 micron; 0.5 dB; 25 percent; 3.5 to 10.5 GHz; 8 dB; DC decoupling capacitor; GaN; GaN HEMT; SiC; SiC substrate; balun; broadband linear push-pull microwave power amplifier; insertion loss; power density; power-added efficiency; small-signal gain; symmetric coupled lines; Broadband amplifiers; Gallium nitride; HEMTs; Impedance matching; Insertion loss; Microwave amplifiers; Microwave devices; Performance loss; Power amplifiers; Silicon carbide;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/7260.950763
