DAC-less PAM4 signal generation using a silicon dual-drive push–pull MZI modulator

In this study, we demonstrate DAC-less PAM-4 signal generation by driving a silicon MZI modulator based on a series push–pull configuration with two independent binary signals of varying amplitudes. Such configuration boosts transfer speed between PAM4 levels, leading to enhanced performance metrics compared to the differential driving scheme. Experimentally, our scheme demonstrated a lower bit-error rate compared to the differential scheme, proving its cost-efficiency and feasibility for PAM4 generation.