Abstract: An adaptive constant current-constant voltage (CC-CV) transition circuit comprises an amplifier, a series-pass device with current sense, a feedback network and a constant current controller to provide a stable and smooth transition between a constant voltage mode and a constant current mode, and vice versa. A voltage regulator loop comprises an amplifier, an optional buffer, a series-pass device with current sense and a feedback network which provides a feedback voltage to the amplifier. A current regulation loop comprises the amplifier, the optional buffer, the series-pass device, the feedback network and a constant current controller comprising a trans-impedence amplifier and a transconductance comparator which generate a current signal to a pseudo-constant bias (PCB) and a voltage signal to the adaptive compensation network (ACN) of the amplifier.