5 4 3 2 1 REVISION HISTORY D 58 56 55 54 53 2 3 4 5 6 7 8 9 57 16 17 19 28 29 PVIN PVIN PVIN PVIN PVIN SW SW SW SW SW SW SW SW NC PVIN PVIN PVIN PVIN PVIN PVIN PVIN PVIN PGND PGND PGND PGND PGND PGND PGND PGND PGND SGND SGND SGND SGND SGND SGND ECO 59 51 50 49 48 47 46 45 52 R4 10 INTVCC U1A LTC3613EWKH S+ 14 1000pF C2 15 S- 18 PGOOD BOOST SNS+ 11 10 SW 35 SW 36 PGND SNS- R10 90.9K R11 60.4K R12 0 22 C7 0.01uF C6 C9 47pF R15 21K 270pF OFF 21 INTVCC 24 R16 OPT 25 R17 0 INTVCC INTVCC VOSNS+ PVIN TRACK/SS ITH SVIN MODE/PLLIN VRNG RT R18 115K SW S+ R7 OPT 0.47uH R9 OPT FP1109-R47 C5 4.7uF 16V 0805 2010 COUT1 100uF 6.3V 1206 COUT2 100uF 6.3V 1206 C 33 VIN PLLIN VIN+ E3 1 32 31 EXTVCC 30 EXTVCC 27 C10 NC 26 1uF RUN C8 0.1uF 50V CIN1 10uF 25V 1210 R13 2.2 CIN2 10uF 25V 1210 CIN3 1210 OPT VIN E4 +CIN4 4.5V - 24V 82uF 25V SANYO 25SVPD82M GND E5 VIN- E6 LOAD STEP CIRCUIT VOUT COUT6 OPT 1206 COUT5 OPT 1206 INTVCC J3 C3 4.7uF 16V 0805 B 1 Q5 R23 10k PULSE GEN E7 SUD50N03-12P 3 JP2 J2 VOUT B MODE 1 2 3 DCM 1.5V / 15A GND S- INTVCC R21 OPT CCM 330uF 2.5V 7343 RS1 0.0015 FSW = 350kHz R19 OPT 1 2 3 23 VOSNS- L1 330uF 2.5V 7343 J1 +COUT4 12 C4 OPT 34 R3 OPT C1 0.1uF 16V INTVCC VOUT SGND 20 D1 CMDSH-3 INTVCC 1 2 R2 0 C JP1 RUN R5 10 +COUT3 13 ON D VO_SNS- VOUT R6 100 VIN VO_SNS+ VOUT R1 100K R14 OPT DATE CHARLIE Z. 08-23-11 E2 44 43 42 41 40 39 38 37 36 E11 E12 APPROVED PRODUCTION E1 R8 100 TRACK DESCRIPTION 3 SW U1B LTC3613EWKH PGOOD REV __ 2 VIN R20 10K GND E8 R22 0.01 2010 LOAD STEP CIRCUIT 5% DUTY CYCLE MAX J4 E10 EXTVCC EXTVCC E9 NOTES: UNLESS OTHERWISE SPECIFIED A 1. WHEN DCR SENSING IS IMPLEMENTED, SHORT RS1 AND R9; DO NOT POPULATE R6 AND R8. 2. ALL RESISTORS ARE IN 0603 ALL CAPACITORS ARE IN 0603 CUSTOMER NOTICE 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. 5 4 3 APPROVALS PCB DES. TECHNOLOGY AK APP ENG. CHARLIE Z. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC FAST, HIGH EFFICIENCY STEP-DOWN REGULATOR SIZE N/A SCALE = NONE 2 DATE: IC NO. LTC3613EWKH REV. 3 DEMO CIRCUIT 1700A Tuesday, August 23, 2011 SHEET 1 1 OF 1 A