In this paper, we consider a novel approach to an electronically controlled optical switch, which would be able to switch digital optical signals from one waveguide into other, suitable for subsequent optical communication. The switch operates based on the two TE mode interference, and the free-carrier injection from the published driver circuit. The switch designs with 1% refractive index decrease and the driver circuit are both consistent with the existing unmodified 45 nm SOI-CMOS foundry process. Our switch designs with 1% refractive index decrease of Si, have a few hundred times smaller area footprint on the chip, a switching time that is several times shorter, and also several times smaller energy consumption, than the optical switch based on a traditional Mach–Zehnder interferometer. Also, our switch shows reasonably good simulated performance. We derived the analytical model from Maxwell's equations for our switch design, and showed the match with the simulated results and also mode solver calculation results.