REVISION HISTORY DESCRIPTION APPROVED ECO REV 1 2 - C12 1st PROTOTYPE PRODUCTION DATE K. SZOLUSHA K. SZOLUSHA OPT Sep 17, 2012 Apr 16, 2013 OUT 1210 * SEE DEMO MANUAL FOR INPUT RANGE C13 OPT 1210 PVIN R12 0 1206 R22 OPT R18 PVIN C1 1µF 100V 1206 35 36 R21 30 124k 1% C10 0.01µF R1 28.7k 350kHz R2 5.1k 21 SW 38 SW 8 SW SW 9 10 NC PWMOUT VMODE RT VC C6 2.2µF 100V 1210 C7 2.2µF 100V 1210 C8 OPT 1210 E4 PGND INTVCC E7 LED+ 67V LED MAX 300mA RS1 R8 25 16.9k 1% 0.82 1% 1206 28 27 E8 C17 OPT LEDR23 M1 Si2328DS OPT 0603 23 R11 R10 0 0805 DIM/SS GNDK DIM PWM GND 33 C16 47nF 300Hz ISN U1 LT3955EUHE 0603 PWM E15 VREF GND 32 ISP 24 OPT PGND E9 R14 OPT 0603 R13 CTRL 37 R20 OPT 0603 31 PGND INTVCC R4 165k 1% 0603 R6 147k 1% C5 2.2µF 100V 1210 R7 1.00M 1% 0603 EN/UVLO 17 SYNC FB PGND E14 SYNC 2 SYNC 16 E6 CTRL 1 PGND SYNC PGND R19 OPT 0603 15 EN/UVLO VIN R3 499k 0603 13 E10 R5 1M 6 OUT R16 OPT 0603 12 E3 PGND OUT C4 2.2µF 100V 1210 R17 OPT Q1 OPT OPT 14 OUT E5 OUT 22µH C3 4.7µF 100V 1210 20 R15 OPT 1206 E2 VIN 5V - 60V* C2 4.7µF 100V 1210 SW OUT C15 OPT 1210 D1 PDS3100-13 GND PVIN 5V - 60V* L1 4 E1 C14 OPT 1210 34 3 OPT 0805 -VMODE R24 R9 100k 0603 INTVCC E11 VMODE SYNC 0 0603 E12 GND E13 C11 1µF 10V GND C9 4.7nF INTVCC E16 INTVCC CUSTOMER NOTICE NOTES: UNLESS OTHERWISE SPECIFIED. 1. RESISTORS ARE 0402 CASE SIZE. 2. CAPACITORS ARE 0603 CASE SIZE. 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. APPROVALS PCB DES. RB APP ENG. KEITH S. TITLE: SCHEMATIC 60VIN 80VOUT LED DRIVER SIZE C:\PADS PROJECTS\2020A(LT3955EUHE)\SCH\2020A_REV2.DSN THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. TECHNOLOGY 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only N/A SCALE = NONE IC NO. LT3955EUHE DATE: Apr 16, 2013 DC2020A SHEET 1 REV. 2 OF 1