ISL6364

Dual 4-Phase + 1-Phase PWM Controller for VR12/IMVP7 Applications ISL6364 The ISL6364 is a dual PWM controller; its 4-phase PWMs control the microprocessor core or the memory voltage regulator, while its single-phase PWM controls the peripheral voltage regulator for graphics, system agent, or processor I/O. The ISL6364 utilizes Intersil’s proprietary Enhanced Active Pulse Positioning (EAPP) modulation scheme to achieve the extremely fast transient response with fewer output capacitors. The ISL6364 is designed to be compliant to Intel VR12/IMVP7 specifications. It accurately monitors the load current via the IMON pin and reports this information via the IOUT register to the microprocessor, which sends a PSI# signal to the controller at low power mode via SVID bus. The controller enters 1- or 2-phase operation in low power mode (PSI1); in the ultra low power mode (PSI2,3), it can further drop the number of phases and then enable the diode emulation of the operational phase. In low power modes, the magnetic core and switching losses are significantly reduced, 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. Today’s microprocessors require a tig htly regulated output v oltage position versus load current (droop). The ISL6364 senses the output curre nt continuou sly by measuring thevoltage acrossthe dedicated current sense resistor or the DCR of the output indu...