5 4 3 2 1 REVISION HISTORY ECO REV DESCRIPTION APPROVED DATE __ 1 PRODUCTION MOLLY Z. 08-09-10 D D U1 LT3686AEDD VIN BD 10uF 63V SANYO 63CE10BS E3 C3 2.2uF 100V 1210 R2 100K JP1 ON OFF GND 6 1 2 3 4 R4 38.3K C 7 C4 0.01uF 5 E5 VIN BOOST EN/UVLO SS SW 10 C1 0.22uF L1 16V 6.8uH MODE/SYNC RT DA MODE/SYNC R1 10K 8 FB GND R7 61.9K (1MHz) 9 VOUT E2 VISHAY IHLP-2020BZ 1 1 +C2 2 D2 MBRM140T1G R3 31.6K C5 OPT 2 E1 VIN 5V - 37V 60V TRANSIENT C6 22uF 10V 1206 3 VOUT 3.3V / 1.2A C E4 GND R6 10K 11 B B NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS ARE IN OHMS, 0402. ALL CAPACITORS ARE IN MICROFARADS, 0402. CUSTOMER NOTICE APPROVALS 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. A TECHNOLOGY KT MOLLY Z. TITLE: SCHEMATIC 5 4 3 IC NO. DATE: REV. LT3686AEDD N/A SCALE = NONE A 37V, 1.2A BUCK REGULATOR SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only 1 DEMO CIRCUIT 1647A Monday, August 09, 2010 2 SHEET 1 1 OF 1