Model OA3MMQM is a broadband 32-Gbaud, lithium-niobate optical modulator driver amplifier. It is suitable for use in Mach Zender interferometer optical modulators and for 400-GB optical long-haul-transponder applications. It can drive 400 GB of data on an existing International Telecommunications Union (ITU) long haul wavelength-division-multiplex (WDM) fiber channel, implemented with 4 channels of 32 Giga-symbol/s data encoded as DP-16QAM modulation schemes. The driver amplifier draws 300 mA from a +5-VDC supply. It provides 20-dB gain with low 7.4-W power dissipation, flat group delay, and 11-ps rise/fall time. The driver amplifier suffers less than 0.6 ps RMS jitter.