The present invention includes a linear driver for Mach-Zehnder modulator (MZM) configured in a differential form with two waveguides carrying two traveling waves. Each waveguide comprises a MZM material configured with either a single segment in 3×MZM length or two split segments with one in 2×MZM length and another one in either 1× or 2×MZM length. By coupling a DC current source supplied with a modulation voltage with each segment thereof for providing electrical modulation signal overlapping with each of the two traveling waves. The modulated traveling waves in the two waveguides then are combined in one output signal by a multimode interference coupler. By properly choosing the configuration of MZM linear segments with optional length ratios, a low power consumption MZM linear driver provides either NRZ or PAM-4 modulation scheme to the input optical signals for telecommunication through silicon photonics.