This paper demonstrates the design of a thermally reconfigurable/tunable operating wavelength of the digital electro-optic D-type flip-flop. The design of the D flip-flop is based on the silicon micro-ring resonator as its core component. The optical modulation technique incurred in the micro-ring resonator utilizes the carrier-injection forward-biased PIN ring waveguide. Micro-heaters are applied to the proposed design with controlled heat generation in order to modulate the operational wavelength, thus allowing the proposed design to operate at varying wavelength. This work proceeds with the simulation and time-varying analysis of the proposed design at the data rate of 1Gbps, and the clocking speed of 5Gbps. Two different operating wavelengths of 1550nm and 1552nm are used to show that the proposed design is wavelength reconfigurable via thermal tuning.