The TPS51621 is a selectable dual or single-phase, fully compliant IMVP-6.5 step down controller with integrated gate drivers. Advanced control features such as D-CAP+ architecture and OSR overshoot reduction provide fast transient response, and lowest output capacitance. The TPS51621 also supports single-phase operation for light loads. The full complement of IMVP-6.5 I/O is integrated into the TPS51621, including VRTT, DPRSLPVR, PSI and output current monitoring (IMON). PSI is used to control the number of active phases. Transitioning into and out of dual-phase mode is exceptionally smooth. Adjustable control of VCORE slew rate and voltage positioning round out the IMVP-6.5 features. In addition, the TPS51621 includes two high-current MOSFET gate drivers to drive high- and low-side N-channel MOSFETs with exceptionally high speed and low switching loss. The TPS51621 is packaged in a space saving, thermally enhanced 40-pin QFN and is rated to operate from -10°C to 105°C.