The ISL6334, ISL6334A control microprocessor core voltage regulation by driving up to 4 interleaved synchronous-rectified buck channels in parallel. This multiphase architecture results in multiplying channel ripple frequency and reducing input and output ripple currents. Lower ripple results in fewer components, lower cost, reduced power dissipation, and smaller implementation area. Microprocessor loads can generate load transients with extremely fast edge rates and requires high efficiency at light load. The ISL6334, ISL6334A utilizes Intersil’s proprietary Active Pulse Positioning (APP), Adaptive Phase Alignment (APA) modulation scheme, active phase adding and dropping to achieve and maintain the extremely fast transient response with fewer output capacitors and high efficiency from light to full load. The ISL6334, ISL6334A is designed to be completely compliant with Intel VR11.1 specifications. It accurately reports the load current via IMON pin to the microprocessor, which sends an active low PSI# signal to the controller at low power mode. The controller then enters 1- or 2-phase operation with diode emulation option to reduce magnetic core and switching losses, yielding high efficiency at light load. After the PSI# signal is de-asserted, the dropped phase(s) are added back to sustain heavy load transient response and efficiency.