The AN8049FHN is a three-channel PWM DC-DC converter control IC that features low-voltage operation. This IC can form a power supply that provides two stepup outputs and one step-down or polarity inverted output with a minimal number of external components. Minimal operating supply voltage of this IC is as low as 1.8 V, so that it can operate from 2 dry-batteries. And also, it is housed in an ultrathin, 4-directionallead SMD-package whose thickness is 0.8 mm maximum and pin-pitch is 0.5 mm therefore it is most suitable for making a power supply small and thin.