LTC1702A Dual 550kHz Synchronous 2-Phase Switching Regulator Controller FEATURES DESCRIPTIO The LTC 1702A is a dual switching regulator controller Pin Compatible with the LTC1702 with Improved optimized for high efficiency with low input voltages. It Current Limit Control includes two complete, on-chip, independent switching regu- Two Sides Run Out-of-Phase to Minimize C IN lator controllers each designed to drive a pair of external N- No External Current Sense Resistors channel MOSFETs in a voltage mode feedback, synchronous Excellent Output Regulation: 1% Total Output buck configuration. The LTC1702A uses a constant-fre- Accuracy quency, true PWM design switching at 550kHz, minimizing Two Independent Controllers in One Package external component size and cost and maximizing load All N-Channel External MOSFET Architecture transient performance. The synchronous buck architecture 550kHz Switching Frequency Minimizes External automatically shifts to discontinuous and then to Burst Component Size Mode operation as the output load decreases, ensuring 1A to 25A Output Current per Channel maximum efficiency over a wide range of load currents. High Efficiency over Wide Load Current Range Less Than 100A Shutdown Current The LTC1702A features an onboard reference trimmed to Small 24-Pin Narrow SSOP Package 0.5% and can provide better than 1% regulation at the U converter outputs. Open-drain logic outputs indicate whether APPLICATIO S either output has risen to within 5% of the final output voltage and an optional latching FAULT mode protects the load if the Microprocessor, DSP Core and I/O Supplies output rises 15% above the intended voltage. Each channel Multiple Logic Supply Generator can be enabled independently with both channels disabled, Distributed Power Applications the LTC1702A shuts down and supply current drops below High Efficiency Power Conversion 100A. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6144194. TYPICAL APPLICATIO Dual Output High Power 3.3V/2.5V Logic Supply V = 5V 10% IN C , C : PANASONIC EEFUE0G181R OUT1 OUT2 + C C : KEMET TS10X337M010AS IN IN D1 10 10F D2 330F D1, D2: MOTOROLA MBR0520LT1 3 D3, D4: MOTOROLA MBRS320T3 1F L1, L2: SUMIDA CEP125-1R0 11.8k 1 24 Q1 TO Q8: FAIRCHILD FDS6670A PV I 1F CC MAX2 1F 1F 2 23 10F BOOST1 BOOST2 3 22 BG1 BG2 Q1 Q2 Q5 Q6 4 21 L1 L2 TG1 TG2 1H 1H V V OUT1 5 20 OUT2 2.5V SW1 SW2 3.3V AT 15A 11.8k AT 15A 6 19 D3 Q3 Q4 D4 Q7 Q8 I PGND + C MAX1 OUT1 1F LTC1702A 180F 7 18 1.2k 1.6k PGOOD1 PGOOD2 4 8 17 + C OUT2 FCB FAULT 10k 820pF 15.8k 1F 180F 1% 680pF 1% 9 16 4 RUN/SS RUN/SS2 1F 10 15 1F COMP1 COMP2 4.99k 4.75k 47k 68k 11 14 1% 1% SGND FB2 V V IN IN 12 13 680pF 27pF 27pF 3300pF FB1 V CC 10k 10k PWRGD2 PWRGD1 FAULT 1702 TA01 1702afa 1 U ULTC1702A ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Note 1) TOP VIEW Supply Voltage 1 24 I PV V ........................................................................................... 7V CC MAX2 CC 2 23 BOOST2 BOOST1 BOOSTn............................................................... 15V 3 22 BG2 BG1 BOOSTn SWn .................................................... 7V 4 21 TG2 TG1 Input Voltage 5 20 SW2 SW1 SWn .......................................................... 1V to 8V 6 19 PGND I MAX1 All Other Inputs ......................... 0.3V to V + 0.3V CC 7 18 PGOOD2 PGOOD1 Peak Output Current < 10s 8 17 FAULT FCB TGn, BGn ............................................................... 5A 9 16 RUN/SS2 RUN/SS1 Operating Temperature Range 10 15 COMP2 COMP1 LTC1702AC ............................................. 0C to 70C 11 14 FB2 SGND LTC1702AI ........................................ 40C to 85C 12 13 V FB1 CC Storage Temperature Range ................. 65C to 150C GN PACKAGE 24-LEAD NARROW PLASTIC SSOP Lead Temperature (Soldering, 10 sec).................. 300C T = 125C, = 100C/ W JMAX JA ORDER PART NUMBER LTC1702ACGN LTC1702AIGN Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: