The RT9262/A 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 RT9262/A 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. The 1.8V to 5V output voltage is set with 2 external resistors. Both internal 2A switch and driver for driving external power devices (NMOS or NPN) are provided.