6-Phase PWM Controller with Light Load Efficiency Enhancement and Current Monitoring The ISL6336B controls microprocessor core voltage regulation by driving up to 6 interleaved synchronous-rectified buck channels in parallel. Multiphase buck converter architecture uses interleaved timing to multiply channel ripple frequency and reduce input and output ripple currents. Lower ripple results in fewer components, lower component cost, reduced power dissipation, and smaller implementation area. Microprocessor loads can generate load transients with extremely fast edge rates and require high efficiency over the full load range. The ISL6336B utilizes Intersil’s proprietary Active Pulse Positioning (APP) and Adaptive Phase Alignment (APA) modulation scheme and a proprietary active phase dropping/adding and diode emulation scheme to achieve extremely fast transient response with fewer output capacitors and high efficiency from light load to full load. The ISL6336B is compliant with Intel’s VR11.1 specification. Features include a pin (IMON) for current monitoring and a Power State Indicator (PSI#) input pin to initiate a proprietary phase dropping and diode emulation scheme for higher efficiency at light load by dropping to 1- or 2-phase operation with optional diode emulation to reduce switching and core losses in the converter. After the PSI# signal is de-asserted, the dropped phase(s) are added back to sustain heavy load transient and efficiency.