REVISION HISTORY This circuit is proprietary to Linear Technology and supplied for use with Linear Technology parts. 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 Applications Engineering for assistance. ECO REV 2 VIN 4 CIN2 1uF 1uF 100V 100V APPROVED 07/21/08 10K 4700pF E6 D5 1 3 1 51.1 1% 3 2 D1 7 8 Co2 Co3 100uF 100uF 100uF 6.3V 6.3V 3.3V / 3A 6.3V E4 SEC. RTN UPS840 2 1 BAS516 50V Q2 R18 PA1277NL 0 VOUT Si4848DY C2 Co1 1 2 D2 R1 4.7uF +VOUT 5 6 2 BAV21W C1 GND E1 T1 R3 C8 5 6 7 8 CIN1 DATE PROTO VOUT VIN E5 2 R20 1 18V - 75V DESCRIPTION 4 6.81K 1% R2 R8 RUN 0.1uF C6 3 105K 1 1 1% 2 OFF 9 3 2 R7 4 R6 8.66K 0 1% R5 3 0.040 INTVCC VC GATE SHDN/UVLO SENSE FB SYNC R15 C15 OPT 0 R11 8 R4 0 7 0 R21 6 499 1% D3 BAS516 SYNC 5 RT 11 JP1 SS RCS1 VIN 10 LT3758EMSE VOUT BAT54C VIN U1 VIN GND OPT OPT ON D4 1 2 3 100pF C3 C16 R9 C10 OPT 10K 220pF E7 U4 4 1 3 2 C4 1 2 PS2801-1 100K LT4430ES6 1uF C7 R14 U3 3 VIN OPTO GND OC COMP FB 1% 6 5 C11 0.47uF OPT C5 4 10nF R12 4.22K 1% C9 R13 36.5K 1% 2200pF C12 270pF 22.1K 250V 1% R10 OPT R16 OPT CONTRACT NO. APPROVALS DRAWN MI DATE 03/14/07 TECHNOLOGY 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 TITLE CHECKED SCH, LT3758EMSE, FLYBACK CONVERTER APPROVED ENGINEER DESIGNER SIZE CAGE CODE DWG NO REV 2 DC1412A Monday, May 04, 2009 SCALE: NONE FILENAME: 1412A-2.DSN SHEET 1 OF 1