5 4 3 2 1 D D SYNC E4 SYNC OR BURST JP1 3 2 1 R2 24k VOUT C1 1500pF 15 SHDN 14 SYNC 11 C2 330pF VC E2 CSS 9 BOOST 6 SW 21 NC 5 NC C4 0.1uF L1 0603 100uH VOUT R5 24k D2 B1100 E5 + C5 27pF NC NC NC CIN 2.2uF 100V 1812 SHDN BURST DEFEAT GND C7 OPT 6032 GND SYNC + VIN NC D1 1N4448HWT 1 2 R3 165k 1% C6 100uF 6.3V 6032 100mOHMS VOUT 3.3V@400mA C E6 GND FB 12 R4 100k 1% 7 13 16 C R1 200k 0603 4 3 17 SHDN E3 VIN 8 * E1 VIN 3.7V - 60V U1 LT3437IFE GND * 80V TRANSIENTS SEE QUICK START GUIDE BIAS 10 C3 0.1uF 0603 B B NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS ARE IN OHMS, 0402. ALL CAPACITORS ARE IN MICROFARADS, 0402. A CUSTOMER NOTICE CONTRACT NO. 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. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 4 3 APPROVALS DRAWN: CHECKED: APPROVED: ENGINEER: KEITH S. DESIGNER: TECHNOLOGY KIM T. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC A HIGH VOLTAGE 500mA 200kHz BUCK CONVERTER WITH BURST MODE SIZE A DATE: DWG NO. DC1232A * LT3437IFE Monday, April 30, 2007 2 SHEET 1 REV A 1 OF 1