4 3 2 2 5 2 D4 PDZ-8.2B 2 1 1 +VIN C3 1000pF T1 PA1006 VB1 R1 560 R3 34k 1 ITH/RUN 2 GND 3 G 6 R7 9 4 7 Q1 FDC2512 3 C1 1uF,10V * 16.9k 3 2 RSC 4.7k SNS 4 VFB=0.8V D1 BAS516 1 2 R2 0 VIN 5 * GND R8 220k 1206 OPT R6 25.5k E2 R10 OPT U1 LTC3803ES6 R4 8.06k GND 1 4 CIN1 1uF,100V 1210 C R5 0 D Q2 Si9803DY 5 6 7 8 1 2 3 +VOUT +VOUT CO1-CO3 100uF,6.3V 1812 GND E3 E4 D3 VB1 BAS516 2 1 1 2 5 6 +VIN E1 36V-72V R9 220k 1206 +VIN D2 BAS516 OPT C2 0.1uF 1 +VOUT 3.3V/ 5V @ 2A GND IF FDC602P IS USED FOR Q2: R2=100 OHMS R5=10 OHMS D1, D2 = BAS516 C 4 8.2V Q3 MMBTA42-7 3 D 1 RCS 0.082 1206 +VOUT B B JP1 VOUT 3.3V 5V 5V OUTPUT, USE SINGLE * FOR 42.2k, 1% RESISTOR. CUSTOMER NOTICE NOTES: UNLESS OTHERWISE SPECIFIED A 1. ALL RESISTORS ARE IN OHMS, 0805. ALL CAPACITORS ARE 0805. 2. INSTALL SHUNT ON JP1 PIN 1 AND 2. 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 CIRUIT 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: GORAN P. DESIGNER: TECHNOLOGY KIM T. TITLE: 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only SCHEMATIC A HIGH EFFICIENCY SYNCHRONOUS NONISOLATED FLYBACK SIZE DWG NO. A DATE: DC781A-1*LTC3803ES6 Friday, October 29, 2004 2 SHEET 1 1 REV A OF 1