A Ka-band Switched-Capacitor RFDAC Using Edge-Combining in 22nm FD-SOI

The paper proposes an RFDAC based on an edge-combining (EC) switched-capacitor power amplifier (SCPA) that triples its clock frequency directly in the output stage to enable a near-mm-wave operation. Another edge-combining based frequency-tripling DLL network increases the system efficiency while a new layout structure accounts for the distributed effects of combining transmission lines. Implemented in 22nm FD-SOI, the prototype achieves P out >21 dBm, DE>36%, SE>22% while operating in the Ka-band at 27.9GHz. Modulation at 2.4Gb/s results in 3.3% EVM and 30.8dBc ACLR.