Waveguide microring resonators (MRRs) is an important component for photonic integrated circuits (PICs). They are successfully used in silicon photonics technology to demonstrate a number of optical functions such as notch filter in all-pass configuration, add-drop configuration for channel multiplexer, delay lines in coupled ring waveguide configuration, ON-OFF switches/modulators by integrating p-i-n/p-n diodes or resistive microheaters, etc. However, when a silicon MRR is subjected to operate at higher power levels, it exhibits bistability posing serious difficulties for most of the non-linear applications, viz. four wave mixing. Bistability in silicon MRRs have been studied widely for all-optical switching applications. In this work, we have proposed a mechanism to electrically control the optical bistability by integrating a phase-shifter with the MRR and obtain enhanced four wave mixing. A solution of parking a laser wavelength around any of the resonances of a MRR and operating at any power levels is explored by integrating a microheater. We have shown with the existing theoretical model that the previous history of phase detuning in a silicon MRR determines the effective gain in stimulated four wave mixing process. The experimental results have been shown to be closely matching with the simulation results. For a MRR of radius 50 µm, an improved stimulated four wave mixing gain of ~ 11.6 dB has been observed while thermo-optically blue-shifting resonances in comparison to that of red-shifting resonances, for a launched pump power of 8.4 mW operating at a slightly off-resonant wavelength λp. The proposed technique can be used in designing actively controlled efficient photon sources in a large-scale integrated quantum photonic circuit operating at λ~ 1550 nm. We also propose optical memory application by utilizing the electrically controlled bistable nature of the MRR. Experimental results supporting the same will be discussed in details.