AAT7631 series is a Power Management IC integrating 3 bucks and 3 LDOs. The device input supply voltage ranges from 2.5V to 5.5V, making the AAT7631 series suitable for single Li-Ion battery-powered devices. AAT7631 or AAT7631A/B/C/D/E provides two level fixed output voltage setting for VDCDC3 buck output using logic High or logic Low levels. AAT7631F/G can be used for adjustable output voltage on VDCDC3.
The highly efficient current mode buck converters operate at 2.25MHz to supply the core, peripheral, I/O and memory rails in a processor based system. All three buck converters can work in forced PWM mode or adaptive PWM / Light Load Mode for maximum efficiency at light load.
AAT7631 or AAT7631A/B/C/D/E/F integrates 2 general purpose 200mA LDO voltage regulators. AAT7631G integrates 2 general purpose 400mA LDO voltage regulators.  Each LDO operates with an input voltage range from 1.5V to 5.5V, allowing them to be supplied from one of the buck converters or directly from the battery. The output voltage of the LDOs can be set with external resistors for flexibility.
Additionally there is a 30mA LDO typically used to provide power in a processor based system to a voltage rail that is always on.