5 4 3 2 1 REVISION HISTORY C3 10uF 50V 1210 100uF 50V 15 13 GND E4 2 SUNCON 50CE100BS SW SW SW PG BOOST EN OUT SS FB C6 10nF NC SYNC NC + C4 VIN VIN VIN GND 10 11 12 VIN RT 5 6 7 C2 0.47uF 0603 DESCRIPTION APPROVED DATE MOLLY Z. 06-29-12 PRODUCTION D VOUT E1 C11 1uF 16V 0603 1 C7 470pF 4 D1 PDS540 R1 1.00M 1% C1 47uF 10V 1210 C5 10pF C8 47uF 10V 1210 E2 VOUT 3.3V / 5A GND 1 16 R2 576k 1% 14 R5 130K 1% (400kHz) 9 8 2 3 C 17 R3 2 2 3 U1 LT3976EMSE E3 REV _ L1 3.3uH IHLP2525CZER3R3M01 D VIN 4.3V - 40V ECO E7 3 2 1 SYNC C JP2 SYNC RT FREQ R6 200K PG E6 EN E5 JP1 ON B OFF 1 2 3 L3 3.3uH XAL5030-332ME L2 1.0uH XAL4020-102ME R7 OPT 0603 VIN VEMI R8 OPT 0603 B C9 10uF 50V 1210 + C10 33uF 50V 50HVP33 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. NOTES: UNLESS OTHERWISE SPECIFIED A 1. ALL RESISTORS ARE 0402. ALL CAPACITORS ARE 0402. APPROVALS PCB DES. JW APP ENG. MOLLY Z. TECHNOLOGY TITLE: SCHEMATIC 5 4 3 A 40V, 5A, 3.3mA MICROPOWER 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 IC NO. N/A SCALE = NONE REV. LT3976EMSE 2 DEMO CIRCUIT 1848A DATE: Wednesday, August 08, 2012 2 SHEET 1 1 OF 1