2021 Volume 18 Issue 11 Pages 20210191
This paper presents a Ka-band 4-way combining power amplifier (PA) implemented in 65nm CMOS process. A T-type power combiner with loaded capacitors is proposed, which is cascaded with transformer-based power combiner to form a hybrid power combiner. The hybrid combiner can combine the output power of 4-way differential PAs into one channel compactly, and makes them achieve optimal load matching. The measured saturation output power (Psat), output 1dB compression point (OP1dB) and maximum power added efficiency (PAEmax) are 23dBm, 18.9dBm and 27% at 35GHz respectively. It achieves a 3dB bandwidth of 30.7GHz-38.5GHz within a core area of 0.26mm2.