A 300MHz to 1200MHz Saturated Broadband Amplifier in GaN for 2W Applications

For power amplifiers to be maximally efficient, it is necessary to operate them in a switch mode which minimizes time in the high power dissipation regions of the transistor characteristic [1, 2, 3]. Typical switch mode amplifiers are narrow band due to matching circuit characteristics. With the advent of GaN based transistors, it is now possible to design moderate power broadband amplifiers without matching circuits [4]. This is primarily due to the large breakdown voltage in GaN [5] which allows a designer to operate transistors directly with a 50 ohm load impedance.