Renesas Electronics Corporation Advanced Linear EAPP Digital 6-Ph PWM Controller for Digital Power with NVM and AUTO Phase Shedding ISL6388HRTZ-T

The ISL6388 is a smart and smallest 6-Phase Green PWM controller, designed to be compliant to Intel VR12.5/VR12 specifications and control the microprocessor core or memory voltage regulator. It includes programmable functions and telemetries for easy use, system flexibility and over-clocking applications using SMBus, PMBus, or I2C interface, which is designed to be conflict free with CPU’s SVID bus and to program NVM banks up to 8 different compensations and system parameters. This minimizes external components and significantly reduces design complexity and PCB area, and simplifies the manufacturing process. The ISL6388 utilizes Intersil’s proprietary Advanced Linear EAPP (Enhanced Active Pulse Positioning) Digital control scheme to achieve the extremely fast linear transient response with fewer output capacitors and overcomes many hurdles of traditional digital approach, which uses non-linear, discrete control method for both voltage loop and current balance loop and runs into beat frequency oscillation and non-linear response. The ISL6388 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, PSI3), it operates in single phase with diode emulation option. 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. In addition, the ISL6388 features auto-phase shedding to optimize the efficiency from light to full load for Greener Environment without sacrificing the transient performance