40A Integrated PowIRstage IR3553 FEATURES DESCRIPTION The IR3553 integrated PowIRstage is a synchronous buck Peak efficiency up to 93.2% at 1.2V gate driver co-packed with a control MOSFET and a Integrated driver, control MOSFET, synchronous synchronous MOSFET with integrated Schottky diode. It is MOSFET and Schottky diode optimized internally for PCB layout, heat transfer and Input voltage (VIN) operating range up to 15V driver/MOSFET timing. Custom designed gate driver and MOSFET combination enables higher efficiency at lower Output voltage range from 0.25V to Vcc-2.5V, or to output voltages required by cutting edge CPU, GPU and 5.5V if internal current sense amplifier is not used DDR memory designs. Output current capability of 40A DC Up to 1.0MHz switching frequency enables high Operation up to 1.0MHz performance transient response, allowing miniaturization Integrated current sense amplifier of output inductors, as well as input and output capacitors VCC under voltage lockout while maintaining industry leading efficiency. The IR3553s superior efficiency enables smallest size and lower solution Thermal flag cost. The IR3553 PCB footprint is compatible with the Body-Braking load transient support IR3550 (60A) and the IR3551 (50A). Diode-emulation high efficiency mode Integrated current sense amplifier achieves superior Compatible with 3.3V PWM logic and VCC tolerant current sense accuracy and signal to noise ratio vs. best-in- Compliant with Intel DrMOS V4.0 class controller based Inductor DCR sense methods. PCB footprint compatible with IR3550 and IR3551 The IR3553 incorporates the Body- Braking feature which Efficient dual sided cooling enables reduction of output capacitors. Synchronous diode emulation mode in the IR3553 removes the zero-current Small 4mm x 6mm x 0.9mm PQFN package detection burden from the PWM controller and increases Lead free RoHS compliant package system light-load efficiency. The IR3553 is optimized specifically for CPU core power APPLICATIONS delivery in server applications. The ability to meet the stringent requirements of the server market also makes Voltage Regulators for CPUs, GPUs, and DDR memory arrays the IR3553 ideally suited to powering GPU and DDR memory designs and other high current applications. High current, low profile DC-DC converters BASIC APPLICATION 94 20 92 18 90 16 IR3553 VIN VCC VCC VIN 88 14 4.5V to 15V 4.5V to 7V 86 12 BOOST 84 10 VOUT PHSFLT PHSFLT SW 82 8 PWM PWM 80 6 BBRK BBRK 78 4 REFIN REFIN CSIN+ 76 2 IOUT IOUT CSIN- 74 0 LGND PGND 0 5 10 15 20 25 30 35 40 Output Current (A) Figure 2: Typical IR3553 Efficiency & Power Loss (See Note 2 on Page 8) Figure 1: IR3553 Basic Application Circuit 1 July 16, 2014 DATASHEET V3.3 Efficiency (%) Power Loss (W)40A Integrated PowIRstage IR3553 PINOUT DIAGRAM ORDERING INFORMATION Package Tape & Reel Qty Part Number PQFN, 25 Lead 3000 IR3553MTRPBF 4mm x 6mm Package Qty Part Number PQFN, 25 Lead 100 IR3553MPBF 4mm x 6mm Figure 3: IR3553 Pin Diagram, Top View TYPICAL APPLICATION DIAGRAM VCC VIN C3 C1 C2 4.5V to 15V 4.5V to 7V 1uF 3 14-16 0.22uF 10uF x 2 R1 VCC VIN IR3553 10k 18 PHSFLT PHSFLT 17 C5 BOOST L1 19 PWM 0.22uF PWM 150nH C6 C7 Gate 22uF 470uF 20 BBRK SW BBRK Drivers VOUT C9 6-11 and 22nF Optional for Current 21 LGND diode emulation Sense R2 C4 setup 2.49k 0.22uF 22 REFIN Amplifier REFIN PGND 12, 13 C8 23 IOUT PGND 1nF 4 IOUT TGND CSIN- CSIN+ 24 1 2 No Connect Figure 4: Application Circuit with Current Sense Amplifier 2 July 16, 2014 DATASHEET V3.3