5 4 3 2 1 HIGH EFFICIENCY L1 7.7UH SUMIDA CDR6D28MN-7R7 U1 LT3481EMSE D D1 DFLS240-7 2 1 GND SANYO 50CV22BS E11 RUN SHDN EXTSS EXTSS C C5 10UF,35V 1206 22UF,50V 5 RUN/SS JP1 1 2 3 4 C9 0.1UF,50V 0603 E12 D2 DFLS240-7 2 1 + C13 22UF,50V C10 0.22UF C14 1UF,50V 1206 C8 330PF 1 2 3 4 E5 C 1 BD 2 BOOST RT 10 VC 9 5 RUN/SS R7 16.9K FB 8 BIAS 7 R8 127K R9 383K PGOOD 6 R10 100K E7 VOUT 5V@2A C16 1UF 10V 0603 E9 GND C15 10UF,10V 0805 R11 19.1K C17 330PF B E10 PGOOD R12 100K C18 0.1UF,50V 0603 E14 2MHz BUCK REGULATOR CUSTOMER NOTICE A NOTES: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS ARE IN OHMS, 0402. ALL CAPACITORS ARE IN MICROFARADS, 0402. 2. INSTALL SHUNT ON JP1 & JP2 PINS 1&2. 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 CIRUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. CONTRACT NO. APPROVALS DRAWN: 4 3 TECHNOLOGY KIM T. TITLE: CHECKED: ENGINEER: KEVIN H. DESIGNER: SIZE A DATE: 2 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only SCHEMATIC 800KHz/2MHz BUCK REGULATOR APPROVED: THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 PGOOD U2 LT3481EDD 11 SANYO 50CV22BS RUN SHDN EXTSS EXTSS R5 19.1K SMALL SIZE 3 SW 4 VIN JP2 C6 22UF,10V 1206 800KHz BUCK REGULATOR SUMIDA CDRH4D22/HP-2R2 E6 VIN 8.5V-22V TRASIENT TO 34V E8 GND E13 GND R4 100K E2 VOUT 3.3V@2A C7 1UF 10V 0603 E4 GND R6 100K L2 2.2UH B GND + C4 R2 102K R3 165K BIAS 7 PGOOD 6 11 GND RT 10 VC 9 FB 8 3 SW 4 VIN E1 E3 1 BD 2 BOOST GND VIN 4.5V-34V C1 0.47UF D R1 60.4K DWG NO. DC857A-2 * LT3481EMSE/EDD Tuesday, April 18, 2006 SHEET 1 REV A-2 1 OF 1 A