DATASHEET ISL6308A FN6669 Rev 0.00 Three-Phase Buck PWM Controller with High Current Integrated MOSFET Drivers September 9, 2008 The ISL6308A is a three-phase PWM control IC with Features integrated MOSFET drivers. It provides a precision voltage Integrated Multi-Phase Power Conversion regulation system for multiple applications including, but not - 1-, 2-, or 3-Phase Operation limited to, high current low voltage point-of-load converters, embedded applications and other general purpose low Precision Output Voltage Regulation voltage medium to high current applications.The integration - Differential Remote Voltage Sensing of power MOSFET drivers into the controller IC marks a - 0.8% System Accuracy Over-Temperature departure from the separate PWM controller and driver (for REF=0.6V and 0.9V) configuration of previous multi-phase product families. By - 0.5% System Accuracy Over-Temperature reducing the number of external parts, this integration allows (for REF=1.2V and 1.5V) for a cost and space saving power management solution. - Usable for Output Voltages not Exceeding 2.3V - Adjustable Reference-Voltage Offset Output voltage can be programmed using the on-chip DAC or an external precision reference. A two bit code programs Precision Channel Current Sharing the DAC reference to one of 4 possible values (0.6V, - Uses Loss-Less r Current Sampling DS(ON) 0.9V,1.2V and 1.5V). A unity gain, differential amplifier is Optional Load Line (Droop) Programming provided for remote voltage sensing, compensating for any - Uses Loss-Less Inductor DCR Current Sampling potential difference between remote and local grounds. The output voltage can also be offset through the use of single Variable Gate-Drive Bias - 5V to 12V external resistor. An optional droop function is also Internal or External Reference Voltage Setting implemented and can be disabled for applications having - On-Chip Adjustable Fixed DAC Reference Voltage with less stringent output voltage variation requirements or 2-bit Logic Input Selects from Four Fixed Reference experiencing less severe step loads. Voltages (0.6V, 0.9V, 1.2V, 1.5V) A unique feature of the ISL6308A is the combined use of - Reference can be Changed Dynamically both DCR and r current sensing. Load line voltage - Can use an External Voltage Reference DS(ON) positioning and overcurrent protection are accomplished Overcurrent Protection through continuous inductor DCR current sensing, while Multi-tiered Overvoltage Protection r current sensing is used for accurate channel-current DS(ON) balance. Using both methods of current sampling utilizes the - OVP Pin to Drive Optional Crowbar Device best advantages of each technique. Selectable Operation Frequency up to 1.5MHz per Phase Protection features of this controller IC include a set of Digital Soft-Start sophisticated overvoltage and overcurrent protection. Capable of Start-up in a Pre-Biased Load Overvoltage results in the converter turning the lower MOSFETs ON to clamp the rising output voltage and protect Pb-Free (RoHS Compliant) the load. An OVP output is also provided to drive an optional crowbar device. The overcurrent protection level is set Applications through a single external resistor. Other protection features High Current DDR/Chipset Core Voltage Regulators include protection against an open circuit on the remote sensing inputs. Combined, these features provide advanced High Current, Low Voltage DC/DC Converters protection for the output load. High Current, Low Voltage FPGA/ASIC DC/DC Converters Ordering Information PART PART TEMP. RANGE PKG. NUMBER MARKING (C) PACKAGE DWG. ISL6308ACRZ* (Note) 6308A CRZ 0 to +70 40 Ld 6x6 QFN (Pb-free) L40.6x6 ISL6308AIRZ* (Note) 6308A IRZ -40 to +85 40 Ld 6x6 QFN (Pb-free) L40.6x6 ISL6308AEVAL1Z Evaluation Platform *Add -T suffix for tape and reel. Please refer to TB347 for details on reel specifications. NOTE: These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. FN6669 Rev 0.00 Page 1 of 28 September 9, 2008ISL6308A Pinout ISL6308A (40 LD 6x6 QFN) TOP VIEW 40 39 38 37 36 35 34 33 32 31 3PH 1 30 BOOT1 2PH 2 29 PHASE1 DAC 3 28 PHASE2 REF 4 27 UGATE2 OFST 5 26 BOOT2 41 GND VCC ISEN2 6 25 COMP PVCC2 7 24 FB 8 23 LGATE2 VDIFF 9 22 PHASE3 RGND 10 21 BOOT3 11 12 13 14 15 16 17 18 19 20 FN6669 Rev 0.00 Page 2 of 28 September 9, 2008 VSEN REF0 OCSET REF1 ICOMP OVP DROOP ENLL ISUM FS IREF PGOOD LGATE3 LGATE1 PVCC3 PVCC1 ISEN3 ISEN1 UGATE3 UGATE1