The ADP3422 is a hysteretic dc-dc buck converter controller to power a mobile processor's core. The optimized low voltage design is powered from the 3.3 V system supply. The output voltage is set by a 5-bit VID code. To accommodate the transition time required by the newest processors for on-the-fly VID changes, the ADP3422 features high-speed operation to allow a minimized inductor size that results in the fastest change of current to the output. To further allow for the minimum number of output capacitors to be used, the ADP3422 features active voltage positioning that can be optimally compensated to ensure a superior load transient response. The output signal interfaces with the ADP3415 MOSFET driver that is optimized for high speed and high efficiency for driving both the upper and lower (synchronous) MOSFETs of the buck converter.