IR3503 DATA SHEET TM XPHASE3 CONTROL IC DESCRIPTION TM The IR3503 control IC combined with an XPHASE3 Phase IC provides a full featured and flexible way to implement a complete VR11.0 and VR11.1 power solution. The IR3503 provides overall system control TM and interfaces with any number of Phase ICs, each driving and monitoring a single phase. The XPhase3 architecture results in a power supply that is smaller, less expensive, and easier to design while providing higher efficiency than conventional approaches. FEATURES 1 to X phase operation with matching Phase IC 0.5% overall system set point accuracy Daisy-chain digital phase timing provides accurate phase interleaving without external components Programmable 250kHz to 9MHz clock oscillator frequency provides per phase switching frequency of 250kHz to 1.5MHz Programmable Dynamic VID Slew Rate Programmable VID Offset or No Offset Programmable Load Line Output Impedance High speed error amplifier with wide bandwidth of 30MHz and fast slew rate of 10V/us Programmable constant converter output current limit during soft start Hiccup over current protection with delay during normal operation Central over voltage detection and latch with programmable threshold and communication to phase ICs Over voltage signal output to system with overvoltage detection during powerup and normal operation Load current reporting capable of interfacing directly to the CPU Single NTC thermistor compensation for correct current reporting, OC Threshold, and Droop Detection and protection of open remote sense line Open control loop protection Programmable VRHOT function monitors temperature of power stage through a NTC thermistor Remote sense amplifier with true converter voltage sensing Simplified VR Ready (VRRDY) output provides indication of proper operation Small thermally enhanced 32L 5mm x 5mm MLPQ package RoHS Compliant ORDERING INFORMATION Device Package Order Quantity 32 Lead MLPQ IR3503MTRPBF 3000 per reel (5 x 5 mm body) 32 Lead MLPQ * IR3503MPBF 100 piece strips (5 x 5 mm body) Samples only Page 1 of 39 February 12, 2010 IR3503 APPLICATION CIRCUIT 12V +12V PSI PSI SHIFT VRRDY RMON IOUT IIN VCCL RMON1 CMON CVCCL PHSIN VOSEN- PHSOUT CLKOUT 33 EXPAD 1 24 VID7 VID7 PSI ROSC 2 23 VID6 VID6 ROSC CSS/DEL 3 22 VID5 VID5 SS/DEL RVDAC CVDAC 4 21 VID4 VID4 VDAC IR3503 RSETPT 5 20 VID3 VID3 VSETPT VDAC RTCMP2 6 19 RTCMP3 VID2 VID2 VDAC BUFF 7 18 VID1 VID1 VN 8 17 VID0 VID0 VDRP RTHERM RTCMP1 RTCMP3 RTCMP2 ENABLE RDRP VRHOT RHOTSET1 RHOTSET3 RCP CCP RFB CFB EAOUT CCP1 CHOTSET RFB1 RHOTSET2 VOSEN+ VOSEN- Note: Pin 33 of IR3503 is the exposed pad located under the IC. It is connected to IC ground Figure 1: IR3503 Application Circuit Page 2 of 39 February 12, 2010 9 32 ENABLE IMON 10 31 VRHOT VRRDY 11 30 HOTSET SHIFT 12 29 VOSEN- IIN 13 28 VOSEN+ VCCL 14 27 VO PHSIN 15 26 FB PHSOUT 16 25 EAOUT CLKOUT