5 4 VIN RUN1 VIN+ 12 VFB2 ITH2 VFB3 C7 1500pF C46 R39 0 41 PGND R5 43.2K R33 10.0K R6 20.0K TK/SS2 R34 20.0K (Opt) C9 1500pF 1000pF 1000pF 1000pF TK/SS3 (Opt) C44 0.01uF E10 A EXTVCC (5.5Vmax) C40 0.1uF R62 100K PGOOD12 PGOOD3 E17 E18 PGOOD12 1 2 3 S2P PGOOD3 OPTIONAL COMPONENTS FOR SINGLE OUTPUT/DUAL PHASE OPERATION SEE QUICK START GUIDE R66 ITH1 (Opt) R26 100 (Opt) 0603 TK/SS1 R67 VFB2 (Opt) (Opt) (Opt) R24 100 SENS2P R23 100 SENS1N R22 100 R68 (Opt) COUT4 100uF 6.3V + X5R COUT5 330uF 2.5V SANYO + COUT6 330uF 2.5V SANYO E3 C48 1uF 6.3V X5R GND E4 (Opt) 0603 SENS2N VO2- SENS2P E24 S2P TG3 S1N CIN6 OPT 4 Q9 RJK0305DPB SW3 B S3P 4 L3 0.78uH IHLP-4040DZ-11 Q10 OPT S1P R21 100 4 OPTIONAL DCR SENSING Q11 RJK0330DPB R59 R57 (Opt) 0603 4 Q12 VO3+ S3N RSNS3 0.002 VOUT3 COUT7 100uF 6.3V (Opt) 0603 X5R COUT8 + 330uF 4V SANYO COUT9 + 330uF 4V SANYO R58 E25 VOUT3 2.5V / 15A E5 C49 1uF 6.3V X5R GND E6 (Opt) 0603 SENS3N VO3- SENS3P OPT E26 OPT DCR SENSE3 WHEN DCR SENSING IS IMPLEMENTED SHORT RSNS1, RSNS2 AND RSNS3 TK/SS2 DO NOT STUFF R21-R26 A CUSTOMER NOTICE RUN2 INTVCC R60 VINF VOUT1 4.5V < VIN < 5.5V CONTRACT NO. LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 4 RSNS2 0.002 VIN CIN5 10uF 16V X5R S2N ONLY 5 VOUT2 S3P R25 100 (Opt) VFB12 E23 OPT DCR SENSE2 R64 VIN VOUT2 1.2V / 15A (Opt) 0603 OPT VIN NOTE: R63 ITH2 R56 VO2+ S2N L2 0.47uH IHLP-4040DZ-11 INTVCC R61 100K VO1E22 C Q8 1 2 3 EXTVCC GND Q6 OPT 4 RJK0330DPB S3N BG3 INTVCC 5 4 Q7 SENS2N SENS1P X5R CIN4 OPT R54 BG3 21 0 R36 C47 1uF 6.3V R55 SENS3P R9 13K 1 2 3 1 2 3 RUN3 34 RUN1 36 38 C23 COUT3 330uF 2.5V SANYO SENS1N 4 5 E14 C22 C8 330pF C45 R35 TK / SS3 C21 CIN3 10uF 16V X5R 4 D3 C26 0.1uF CMDSH-3 TG3 19 SW3 20 SENS3N TK / SS2 E15 C3 (OPT) TG2 BG2 R29 4.7 PGOOD3 16 PGOOD3 11 SGND + VIN 1 2 3 (Opt) VOUT3 B 23 EXTVCC PGOOD12 17 PGOOD12 COUT2 330uF 2.5V SANYO SENS1P SW2 BOOST3 18 EXTVCC SENSE3- R32 20.0K 15 ITH3 VOUT3 C25 D2 0.1uF CMDSH-3 BG2 28 3 E16 R28 4.7 8 TK/SS1 TK / SS1 R8 10K VIN Q5 RJK0305DPB TG2 26 SW2 27 SENSE3+ R31 24.9K + SW1 BOOST2 25 14 VFB3 COUT1 100uF 6.3V X5R OPT DCR SENSE1 TG1 BG1 BG1 30 13 ITH2 C6 220pF VOUT3 Q4 OPT RJK0330DPB 5 VFB2 VOUT1 1.8V / 15A E1 E2 (Opt) 0603 1 2 3 R4 20.0K 10 ITH1 SENSE2- (Opt) (Opt) ITH1 7 R46 C43 JP3 C2 47pF R3 10.0K TG1 32 SW1 31 6 3 4 Q3 C24 D1 0.1uF CMDSH-3 VO1+ E21 R52 R27 4.7 9 VFB1 RUN3 2 OFF 4 R53 RSNS1 0.002 (Opt) 0603 5 R38 0 (Opt) VIN 24 INTVCC 22 DRVCC12 29 BOOST1 33 2 TK/SS3 SENSE2+ R45 RUN3 1 R51 (Opt) 0603 1 2 3 TK/SS3 16V VOUT1 S1N 5 TK/SS2 VOUT2 E13 U1 LTC3853EUJ SENSE1- VIN RUN3 40 TK/SS1 1 TK/SS2 RUN3 5 TK/SS1 RUN2 35 R7 15K FREQ C4 C5 1500pF 330pF 5 (Opt) MODE 37 R2 20.0K R44 C42 (Opt) S1P L1 0.56uH IHLP-4040DZ-11 Q2 OPT D VIN- E20 4 C11 4.7uF RUN2 ILIM 39 3 JP2 4 Q1 RJK0305DPB INTVCC RUN1 R50 OPT RUN2 SENSE1+ (Opt) R47 2.55K MODE 4 RUN2 1 ON 2 OPT C1 22pF 1 2 3 R1 24.9K R43 + GND 5 R49 E12 CIN7 180uF 16V 1 2 3 VIN RUN2 VIN 6.5V - 14V E7 E8 C10 0.1uF R65 0 CIN2 OPT 5 INTVCC CIN1 10uF 16V X5R VIN 5 R40 1K C50 1000pF R10 2.2 1 2 3 E9 VFB12 VINF R48 10.0K 5 4 SYNC R37 0 C 400kHz E19 VIN VIN 5 VOUT1 D ON INTVCC MODE JP4 (Opt) VIN 1 2 3 3 R42 C41 (Opt) JP1 BURST/SYNC FORCE CONTINUOUS RUN1 3 2 5 (Opt) PULSE SKIP 1 2 3 R41 2 OFF 1 1 RUN1 1 OFF 2 INTVCC MODE E11 ON 3 3 2 APPROVALS DRAWN AntoninaK DATE 10/26/07 CHECKED TECHNOLOGY TITLE LTC3853EUJ High Current Polyphase 3-Output Step-Down Supply with Tracking APPROVED ENGINEER Johan Stydom 10/26/07 DESIGNER Monday, September 08, 2008 SIZE 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 CAGE CODE SCALE: DWG NO REV DC1349A FILENAME: SHEET 1 1 2 OF 1