Xiqing Liang, Bingzheng Yang, Hongxin Tang, Xun Luo: A 0.6-to-0.9GHz, 28.06dBm Pout, 43.73% SE, 6-Phase Switched-Capacitor Power Amplifier Using In-Cell Digital Waveform Synthesis for the 2<sup>nd</sup>-, 3<sup>rd</sup>-, and 4<sup>th</sup>-Harmonic Suppression. ISSCC 2026: 570-572