1 2 3 4 5 6 7 8 REVISION HISTORY ECO INTVCC DATE YI S. 03/24/11 2 4 3 1 E5 JP3 VIN+ NOTE:SET RSENSE FILTER TIME CONSTANT O .6nH/RSENSE FOR 2010 PACKAGE. R1 SYNC J1 CIN1 180uF 16V OPT R48 4.5V - 14V + J2 2 VIN GND 0 C37 R27 OPT 30.1k E6 VIN R26 RUN1 VIN- OPT 1 2 3 C38 JP1 R28 R29 [2] OPT R30 [2] Q1 BSC050NE2LS OPT CIN2 CIN4 10uF 1210 OPT 1210 Q5 OPT 5 6 7 8 OFF 5 6 7 8 ON U1 R31 [2] C42 R32 20k VFB1 4 100pF R33 20k VFB2 5 ITH2 6 C43 VOUT1 R34 E10 220pF R35 OPT R36 ITH1 3 C44 TRK/SS2 7 1.5nF RUN2 [2] 0 VIN OPT BG1 VFB1 VIN VFB2 INTVCC ITH2 BG2 TK/SS2 10 PGND RUN2 BOOST2 ILIM 12 TG2 EXTVCC 13 C47 BOOST1 ITH1 11 TK/SS2 R37 TK/SS1 SW2 PGOOD 0.1uF R38 RUN2 ON OFF 3 C48 R41 OPT OPT D1 R9 0 INTVCC 21 CMDSH-3 VINF 20 C11 2.2 INTVCC 0.1uF E2 C49 R43 OPT 20k J4 GND B 5 6 7 8 E12 VIN 0 Q3 BSC050NE2LS CMDSH-3 14 9 S2+ C21 4 C15 0.1uF CIN3 CIN5 10uF 1210 OPT 1210 Q7 OPT 4 E13 VL2- VO2+ L2 [2] [2] RS2 S2- J5 VSW2 R40 [2] Q8 OPT 4 VOUT2 R51 [2] S2+ [2] R62 [2] R53 2010 S2- COUT4 100uF 1210 COUT5 COUT6 + 330uF + 330uF 2.5V 2.5V 7343 7343 OPT VOUT2 1.2V / 15A C36 4.7uF 6.3V 0805 J6 GND E14 BSC010NE2LS VO2C R54 R44 OPT GND S1- VIN Q4 OPT 1.5V / 15A D2 R25 8 C32 4.7uF 6.3V 0805 VO1- 4 INTVCC VOUT1 COUT3 + 330uF 2.5V 7343 OPT 4.7uF 0805 17 15 R47 S1+ Q2 BSC010NE2LS 2010 COUT2 + 330uF 2.5V 7343 INTVCC 18 16 4 R61 [2] COUT1 100uF 1210 R18 C17 19 R39 [2] R42 C SENSE2- 29 OPT 1 2 JP2 SENSE2+ 4 23 22 Q6 OPT [2] 5 6 7 8 1.5nF TG1 0.1uF 1 2 3 C41 B RUN1 24 1 2 3 2 VOUT1 R45 [2] 1 2 3 27 SW1 C20 5 6 7 8 RUN1 FREQ VSW1 [2] J3 28 S1+ 5 6 7 8 26 [2] SENSE1+ 1 2 3 0.1uF MODE/PLLIN 5 6 7 8 OPT 25 R10 RS1 1 2 3 C2 VO1+ L1 [2] 1 5 6 7 8 R2 SENSE1- 1 2 3 0 TRK/SS1 E11 VL1- 4 1 2 3 C14 R3 SGND E9 4 1 2 3 S1- LTC3869EUFD TK/SS1 A VIN VIN C1 1 0 APPROVED 1ST PROTOTYPE MODE 10.0K A DESCRIPTION 1 PS BM CCM R4 E1 REV 0 E3 INTVCC EXTVCC EXTVCC C50 R46 1uF 100K E4 VINF OPTIONAL JUMPERS FOR SINGLE OUTPUT/DUAL PHASE OPERATION INTVCC PGOOD PGOOD R60 R49 ITH1 OPT ITH2 OPT R50 VFB1 STUFF R60 WITH 0 OHMS FOR 4.6V<VIN<5.5V VFB2 OPT R52 TRK/SS1 NOTES:UNLESS OTHERWISE SPECIFIED. [2] ASSY FSW -A R SENSE -B DCR SENSE 400kHz 300kHz R10 102k 75k 1 X2 OPT R55 L1, L2 VITEC 59PR9875, 0.4uH VISHAY IHLP4040DZ11, 0.56uH RS1, RS2 0.002 0 R45, R51 R61, R62 R29, R30, R39, R40 C14, C15 C41, C44 CUSTOMER NOTICE R31, R35 OPT OPT 100 1nF 1nF 5.9k 1.58k 0 OPT 220nF 1.5nF 5.9k CONTRACT NO. LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A APPROVALS CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. MI VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL ENG. YI S. 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. 3 TOOLING HOLES TECHNOLOGY 4 5 6 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC DUAL PHASE / DUAL OUTPUT SYNCHRONOUS BUCK CONVERTER SIZE N/A 2 RUN2 OPT 3. ALL CAPACITORS AND RESISTORS ARE 0603. 1 X1 TRK/SS2 RUN1 1. DO NOT APPLY LOAD FROM THE VO1+ TO VO1- OR FROM THE VO2+ TO VO2- TURRETS. THESE ARE ONLY INTENDED TO KELVIN SENSE THE OUTPUT VOLTAGE ACROSS COUT1 AND COUT4. D 1 DATE: 7 IC NO. REV LTC3869EUFD DEMO CIRCUIT 1807A Friday, March 25, 2011 SHEET 8 1 1 OF 1 D