LTC3730 3-Phase, 5-Bit Intel Mobile VID, 600kHz, Synchronous Buck Controller FEATURES DESCRIPTIO The LTC 3730 is a PolyPhase synchronous step-down 3-Phase Current Mode Controller with Onboard MOSFET Drivers switching regulator controller that drives all N-channel 5% Output Current Match Optimizes Thermal external power MOSFET stages in a phase-lockable fixed Performance and Size of Inductors and MOSFETs frequency architecture. The 3-phase controller drives its Operational Amplifier Accomodates Mode Switching output stages with 120 phase separation at frequencies of 1% V Accuracy Over Temperature up to 600kHz per phase to minimize the RMS losses in both REF Reduced Input and Output Capacitance the input and output filter capacitors. The 3-phase tech- Reduced Power Supply Induced Noise nique effectively triples the fundamental frequency, im- V Programmable from 0.6V to 1.75V (IMVP III) OUT proving transient response while operating each controller 10% Power Good Output Indicator at an optimal frequency for efficiency and ease of thermal 250kHz to 600kHz Per Phase, PLL, Fixed Frequency design. Light load efficiency is optimized by using a choice TM PWM, Stage Shedding or Burst Mode Operation of output Stage Shedding or Burst Mode technology. OPTI-LOOP Compensation Minimizes C OUT An internal operational amplifier provides mode selectable Adjustable Soft-Start Current Ramping output voltage programming in conjunction with the inter- 4V, V , Undervoltage RUN/SS Reset/Reattempt Circuit IN nal VID voltage control DAC. Short-Circuit Shutdown Timer with Defeat Option Overvoltage Soft Latch Soft-start and a defeatable, timed short-circuit shutdown Small 36-Lead Narrow (0.209) SSOP Package protect the MOSFETs and the load. Current foldback provides protection for the external MOSFETs under U short-circuit or overload conditions. APPLICATIO S , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode, OPTI-LOOP and PolyPhase are registered trademarks of Linear Technology Corporation. Tablet Computers Stage Shedding is a trademark of Linear Technology Corporation. All other trademarks are High Performance Notebook Computers the property of their respective owners. Protected by U.S. Patents including 5481178, 5929620, 6177787, 6144194, 6100678, 5408150, 6580258, 6462525, 6304066, 5705919. High Output Current DC/DC Power Supplies TYPICAL APPLICATIO V IN V 5V TO 28V CC V TG1 CC + 1H 4.5V TO 7V 0.003 22F LTC3730 10F SW1 35V BOOST1 BG1 BOOST2 BOOST3 + 0.1F SENSE1 SENSE1 SW3 SW2 SW1 V IN TG2 1H POWER GOOD INDICATOR PGOOD V 0.003 OUT OPTIONAL SYNC IN PLLIN SW2 1.2V 50A BG2 PLLFLTR PGND 5 VID BITS VID0-VID4 + SENSE2 680pF SENSE2 V IN I TG3 TH 1H 0.003 5k RUN/SS SW3 0.1F SGND BG3 EAIN 100pF + AMPOUT SENSE3 + C SENSE3 OUT IN + 470F IN x4 3730 F01 2.5V Figure 1. High Current Triple Phase Step-Down Converter 3730fa 1 U ULTC3730 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW Topside Driver Voltage (BOOST ) Range .. 38V to 0.3V ORDER PART N VID1 1 36 VID0 Switch Voltage (SW ) Range........................ 32V to 5V NUMBER N 2 PLLIN 35 PGOOD Boosted Driver Voltage (BOOST SW ) .... 7V to 0.3V N N 3 34 BOOST1 LTC3730CG PLLFLTR Peak Output Current <1ms (TG , BG ) ..................... 5A N N 4 33 TG1 FCB Supply Voltage (V ), PGOOD + CC IN 5 32 SW1 Pin Voltage Range ....................................... 7V to 0.3V IN 6 31 BOOST2 7 30 TG2 PLLIN, RUN/SS, PLLFLTR, FCB Voltages .. V to 0.3V AMPOUT CC 8 29 SW2 EAIN I Voltage Range ..................................... 2.4V to 0.3V TH SGND 9 28 V CC Operating Ambient Temperature Range ....... 0C to 70C + SENSE1 10 27 BG1 Junction Temperature (Notes 2, 7) ....................... 125C 11 26 PGND SENSE1 Storage Temperature Range ..................65C to 150C + 12 25 BG2 SENSE2 Lead Temperature (Soldering, 10 sec).................. 300C SENSE2 13 24 BG3 SENSE3 14 23 SW3 + 15 TG3 SENSE3 22 16 21 BOOST3 RUN/SS I 17 20 VID4 TH VID2 18 19 VID3 G PACKAGE 36-LEAD PLASTIC SSOP T = 125C, = 95C/W JMAX JA Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: