ISL6326B

Description

The ISL6326B controls microprocessor core voltage regulation by driving up to 4 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. The ISL6326B utilizes Intersils proprietary Active Pulse Positioning (APP) and Adaptive Phase Alignment (APA) modulation scheme to achieve the extremely fast transient response with fewer output capacitors. Todays microprocessors require a tightly regulated output voltage position versus load current (droop). The ISL6326B senses the output current continuously by utilizing patented techniques to measure the voltage across the dedicated current sense resistor or the DCR of the output inductor. The sensed current flows out of FB pin to develop the precision voltage drop across the feedback resistor for droop control. Current sensing also provides the needed signals for channel-current balancing, and overcurrent protection. A programmable integrated temperature compensation function is implemented to effectively compensate for the temperature coefficient of the current sense element. The current limit function provides the overcurrent protection for the individual phase. A unity gain, differential amplifier is provided for remote voltage sensing. Any potential difference between remote and local grounds can be completely eliminated using the remote-sense amplifier. Eliminating ground differences improves regulation and protection accuracy. The thresholdsensitive enable input is available to accurately coordinate the start up of the ISL6326B with any other voltage rail. Dynamic-VID technology allows seamless on-the-fly VID changes. The offset pin allows accurate voltage offset settings that are independent of VID setting.