5 4 3 2 1 REVISION HISTORY ECO REV DESCRIPTION APPROVED PRODUCTION 2 VK DATE 9-01-15 Q1 D SI4491EDY 3 2 5 1 E1 VIN R2 + C9 47uF C10 4.7uF 1210 R1 511K 4 3V - 17V R5 37.4K C8 OPT 0.01 1210 + C11 E2 GND R3 133K R4 1MEG 4 E9 5 24 C 6 8 E10 R12 OPT 13 R7 IN INDIS IN INDIS CLP SW GATE SW FBSYS SW PFI BOOST INTVCC CAP 510K E5 11 CAPGD R8 CAPGD FBCAP INTVCC ITH 510K E6 12 /PFO 7 2 1 3 OFF INTVCC ILIM RUN 1 ON /PFO 2 17 L1 7.2uH 18 C 19 20 C1 0.1UF 40V MAX 15 3 R10 322K 10 21 INTVCC C2 4.7uF 0805 C4 22pF R9 402K PGND NC PGND NC 22 23 E7 R11 5.11K GND 1 2A 2 3 3A 4 4A JP2 APPROVALS TECHNOLOGY LT VK TITLE: SCHEMATIC SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 3 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only BIDIRECTIONAL HIGH VOLTAGE BACKUP CONVERTER 1. ALL RESISTORS AND CAPACITORS ARE 0603. 4 C14 10uF 1210 CAP ILIM_BUCK CUSTOMER NOTICE NOTE: UNLESS OTHERWISE SPECIFIED C15 1uF 100V 0805 + C5 + C6 1000uF OPT 50V C3 470pF 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 APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. A C7 OPT 9 14 E8 40V BACKUP B 25 JP1 5 GND 16 RUN PGND B E4 U1 LTC3643EUDD R6 5.11K GND PFI LOAD C13 10uF 1210 C12 10uF 1210 47uF D E3 5V SYSTEM BUS N/A SCALE = NONE 2 DATE: IC NO. LTC3643EUDD DEMO CIRCUIT 2220A REV. 2 Tuesday, September 01, 2015 SHEET 1 1 OF 1 A