The active droplet oscillation is a method previously proposed to detach the droplet at currents below the transition current. In this method, a droplet oscillation is actively excited when the current is switched from the exciting peak level to base level. The downward momentum of the droplet is utilized to enhance the droplet detachment. In this work, the current waveform is modified to achieve stronger droplet oscillation with lower average current. The critical change is to separate the droplet growing and exciting processes such that the two processes can be controlled independently. The heat input can thus be reduced, and stronger droplet oscillation is obtained. A further optimized current waveform is proposed to maximize the droplet oscillation energy despite the growing current level.