5 4 3 2 1 SHOULD BE PLACED BETWEEN VIN1 AND GND1. C12 ** C2 SHOULD BE PLACED BETWEEN VIN2 AND GND2. THESE CAPACITORS MUST BE PLACED AS CLOSE AS POSSIBLE TO LT8641. GND EN/UV E1 OPT 4 VIN R1 1M E2 + C1 C11 4.7uF 100V 1206 22uF 100V R6 OPT ** C2 0.1uF 100V 13 ** C12 0.1uF 100V SUNCON 100CE22BS 14 E6 17 VCC 2 JP1 E5 VCC 1 2 3 4 5 6 7 8 16 C7 1uF 25V SYNC SPREAD SPECTRUM 15 R2 18.2K (2MHz) PULSE SKIPPING BURST TR/SS E7 GND C8 0.1uF E9 FB1 MPZ2012S300A B VEMI 5.5V - 65V C14 0.1uF 100V 0603 BST 3 L1 C4 2.2uH 0.1uF 16V IHLP2525CZER2R2M01 8 SW 9 SW 21 SW 22 SW EN/UV SYNC BIAS RT PG FB C6 100uF 10V 1210 R7 1 C9 1uF E4 R4 20 R5 191k C5 * GND C 100k R3 19 VOUT 5V / 3.5A 1M 10pF PG E8 B VIN C3 4.7uF 100V 1210 C10 4.7uF 100V 1210 NOTES: UNLESS OTHERWISE SPECIFIED LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; TECHNOLOGY HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED TITLE: SCHEMATIC CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. 1. ALL RESISTORS ARE 0603. ALL CAPACITORS ARE 0603. SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 E3 C13 10uF 0805 10V 0 CUSTOMER NOTICE A SEE DEMO MANUAL VOUT INTVCC TR/SS * L2 0.22uH IHLP1212BZERR22M11 VEMI E10 VIN2 6 7 GND1 10 GND1 11 GND2 GND2 SYNC C D VIN1 GND VIN 5.5V - 65V 18 D U1 LT8641EUDC 4 3 N/A DATE: 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only 65V, 3.5A MICROPOWER SYNCHRONOUS STEP-DOWN SILENT SWITCHER IC NO. REV. LT8641EUDC 1 DEMO CIRCUIT 2373A Wednesday, February 17, 2016 2 SHEET 1 1 OF 1 A