8-W 2-Stage GaN Doherty Power Amplifier Module on 7 × 7 QFN for the 5G N78 Band

This paper presents a 2-stage GaN Doherty power amplifier module (DPAM) on a compact $7\times 7$ quad flat no-lead (QFN) package, designed for the needs of 5G massive MIMO base transceiver systems. The interstage and input matching networks employ high-quality factor integrated passive devices (IPDs) to achieve a small form factor. This multi-chip module consists of three GaN-HEMT bare dies used for the driver stage, carrier amplifier, and peaking amplifier. Additionally, two IPD dies are included for the interstage and input matching networks. The external load network is developed using a printed circuit board (PCB). Utilizing a 5G NR signal of 100 MHz bandwidth and a 9.3 dB PAPR within the 3.4–3.8 GHz band, the developed DPAM demonstrated a power gain exceeding 26.8 dB and a power-added efficiency (PAE) greater than 37.8% at a 39 dBm average output power.