5 4 3 2 1 REVISION HISTORY ECO REV __ E1 VIN VIN INTVCC 16V - 60V J2 GND C2 2.2uF 100V 1812 C1 2.2uF 100V 1812 2.2 C3 56uF/63V + DATE VICTOR K. 04-16-12 VOUT 63HVH56M SUN ELECT. R3 OPT C4 0.1uF 100V INTVCC R2 0 30.1K E2 D R6 R4 100k GND C5 10pF U1 R5 511K 0805 LTC3891EUDC PGOOD VOUT 17 9 15 4.7uF 0805 19 R12 OPT 4 VIN 1 ON OFF 8 C9 0.1uF 2 2 3 3 16 C11 OPT R16 57.6K JP1 C12 R17 TRACK/SS RUN SENSE- SENSE+ BOOST 1 PGND TG PLLIN/MODE B INTVCC JP2 MODE 1 2 R20 100K ILIM INTVCC BG OPT R21 4 PULSE SKIP 5 6 BURST 100 C19 OPT VIN 1812 OPT Q4 Q1 4 VOUT 11 13 RJK0653DPB OPT Q3 Q2 4 R19 FCM 3 DFLS1100 RJK0651DPB 4 L1 RS1 0.003 10uH 2512 E6 VOUT J3 VOUT C22 C21 C20 4 1 2 3 C18 OPT SGND 1K C10 2.2uF 100V VIN 21 E8 10 D1 INTVCC C13 0.1uF SW 18 R15 2 SGND C14 47pF R18 SYNC 12 C R13 6 ITH SGND 0 C8 2.2pF 15.4K 4.7nF R10 5 5 E5 C6 1 2 3 TRACK RUN INTVCC INTVCC 14 C7 1uF R11 OPT R14 1 Meg 0805 EXTVCC VFB 5 OPT E4 PGOOD R7 35.7K 20 7 C15 10uF 1206 + OPT 7343 1 2 3 EXTVCC R8 0 FREQ 5 R9 VIN 1 2 3 E3 C APPROVED PRODUCTION R1 5 D VIN J1 DESCRIPTION 2 12V / 15A C16 + 150uF 16V 16SVPC150M C17 1uF B J4 E7 GND GND OPT GND E9 GND E10 CUSTOMER NOTICE A LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APP ENG. APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. NOTES: 1. ALL RESISTORS AND CAPACITORS ARE 0603 2. INSTALL SHUNTS AS SHOWN. 3. FOR SYNCHRONIZATION REMOVE JUMPER JP2 'MODE' AND CONNECT SOURCE OF THE SYNC SIGNAL TO TERMINALS E8 'SYNC' AND E9 'GND' 5 APPROVALS THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 4 3 TECHNOLOGY LT VICTOR K 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 LOW QUIESCENT CURRENT HIGH VOLTAGE STEP-DOWN CONVERTER SIZE N/A SCALE = NONE 2 DATE: IC NO. LTC3891EUDC REV. DEMO CIRCUIT 1940A Monday, April 16, 2012 SHEET 1 1 2 OF 1 A