DATASHEET ISL8121 FN6352 Rev 2.00 3V to 20V, Two-Phase Buck PWM Controller with Integrated 4A MOSFET Drivers October 27, 2009 The ISL8121 is a two-phase buck PWM controller Features featuring an input voltage range of 3V to 20V and Integrated Two-Phase Power Conversion integrated MOSFET drivers. Precision voltage regulation is provided for point-of-load and other high- Precision Output Voltage Regulation current applications that require efficient and compact - 0.8% System Accuracy Over-Temperature implementation. Multiphase buck converter (Industrial) architecture uses interleaved timing to multiply - Differential Remote Voltage Sensing for channel ripple frequency allowing smaller filter Increased Voltage Sensing Accuracy inductors and reducing input and output ripple currents due to the ripple cancellation effect. Lower ripple Shunt Regulator for Wide Input Power Conversion results in fewer input and output capacitors. Smaller - 5V and Higher Bias and low cost transistors can be used resulting from the - Up to 20V Power Down-Conversion higher efficiency and reduced power dissipation. Precision Channel Current Sharing The ISL8121 offers an internal 0.6V reference with a - Loss-Less r Current Sampling DS(ON) system regulation accuracy of 0.8% (Industrial Temperature range), an optional external reference Integrated High Capable 4A Drivers input, and user-adjustable switching frequency. Unity 0.6V Internal Reference gain differential amplifier targeted at remote voltage Full Spectrum Voltage Tracking sensing capability enhances the regulation. A power - Coincidental, Ratiometric, or Offset good signal (PGD) is issued when the output voltage is within the regulated window. An internal shunt Sequential Start-up Control regulator with optional external connection capability Selectable Switching Frequency up to 2MHz Per extends the operational input voltage range. For Phase applications requiring voltage tracking or sequencing, the ISL8121 offers a host of possibilities, including Fast Transient Recovery Time coincidental, ratiometric, or offset tracking, as well as Overcurrent Protection sequential start-ups, user adjustable for a wide range Overvoltage Protection of applications. Capable of Start-up in a Pre-Biased Load Additional features include overvoltage and QFN Packages: overcurrent protection. Overcurrent protection can be - QFN - Compliant to JEDEC PUB95 MO-220 tailored to various applications with no need for - QFN - Quad Flat No Leads - Package Outline additional parts. The ISL8121 uses cost and space- saving r sensing for channel current balance, - Near Chip Scale Package footprint, which DS(ON) dynamic voltage positioning, and overcurrent improves PCB efficiency and has a thinner profile protection. Channel current balancing is automatic and Pb-Free Available (RoHS Compliant) accurate with the integrated current-balance control system. Applications General Purpose High Current DC/DC Converters High Current, Low Voltage FPGA/ASIC DC/DC Converters Telecom System FN6352 Rev 2.00 Page 1 of 26 October 27, 2009ISL8121 Ordering Information PART NUMBER PART TEMP. RANGE PACKAGE PKG. (Notes 1, 2, 3) MARKING (C) (Pb-Free) DWG. ISL8121IRZ 81 21IRZ -40 to +85 24 Ld 4x4 QFN L24.4x4C NOTES: 1. Add -T suffix for tape and reel. Please refer to TB347 for details on reel specifications. 2. 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. 3. For Moisture Sensitivity Level (MSL), please see device information page for ISL8121. For more information on MSL please see techbrief TB363. Pin Configuration ISL8121 (24 LD QFN) TOP VIEW 24 23 22 21 20 19 VSEN- 1 18 PHASE1 VSEN+ 2 17 ISEN1 VMON 3 16 LG1 25 GND 15 VDIFF 4 PVCC FB 5 14 LG2 COMP 6 13 ISEN2 78 9 1011 12 FN6352 Rev 2.00 Page 2 of 26 October 27, 2009 VREG REFTRK VCC SS EN FS BOOT2 PGD UG2 BOOT1 PHASE2 UG1