The RT9263 is a compact, high efficient, step-up DC/DC converter with an adaptive current mode PWM control loop, providing a stable and high efficient operation over a wide range of load currents. It operates in both continuous and discontinuous current modes in stable waveforms without external compensation. The low start-up input voltage below 1V makes RT9263 suitable for 1 to 4 battery cell applications providing up to 400mA output current. The 550kHz high switching rate minimized the size of external components. Besides, the 17A low quiescent current together with high efficiency maintains long battery lifetime.