1 2 PVIN * PVIN TP1 C1 1uF 50V GND + TG2 17 SW2 20 OVP2 11 TG2 CAP1 15 LED1 14 CAP1 SW2 6 FADJ OVP2 1 JP2 FADJ C3 2.1MHz ADJUST 1 3 2 R18 100K Frequency Adjust R12 18.2K C4 1000PF R14 18.2K C5 1000PF R15 18.2K 9 VC1 TG1 13 SW1 16 8 VC2 7 VC3 OVP1 12 LED1 TG1 SW1 OVP1 3 TG3 1 1 LED3 0.51 2 PVIN L1 2 15uH 1 D1 3 LED2L+ LED2L- 3 C2 1uF 50V (OPT) LED1H+ 2 BOOST TP19 TP20 R1 7.15M TP3 Q1 LED1HTP4 OVP1 R2 0.51 JP4 MODE BUCK/BOOST 2 LED1L+ LED1L- 3 JP3 MODE BUCK/BOOST 2 BOOST TP17 TP18 R10 191K 3 2 1000PF TP11 TP12 OVP2 C11 2.2uF 25V 29 GND VREF R11 7.15M R13 R17 191K 27 PWM3 TP10 PVIN C6 1uF 50V (OPT) Q2 LED2H- 1 LED2 1 D2 LED2H+ PVIN TP9 2 15uH C12 2.2uF 25V 3 TP8 L2 PVIN PWM2 PWM3 1 PWM1 28 PWM2 CAP2 BOOST TP21 TP22 1 CAP2 19 LED2 18 R22 R23 R24 (OPT) (OPT) (OPT) PWM1 OVP3 A BUCK/BOOST 2 SW3 PVIN 3 CTRL3 TP7 3 JP5 MODE TG2 1 TP6 TG3 LED3L- 1 CTRL3 OVP3 LED3L+ TG1 CTRL2 5 CTRL1 4 CTRL2 TP5 TP13 TP14 2 R21 191K SW1 CTRL1 C7 0.1uF LED3 R19 7.15M 0.51 LED2 3 R4 R5 R6 R7 R8 R9 100K 100K 100K 100K 100K 100K TG3 24 SW3 21 OVP3 10 CAP3 C8 1uF 50V (OPT) D3 R20 LED1 VREF R3 10K CAP3 22 LED3 23 26 SHDN 2 VREF 15uH Q3 LED3H- CAP2 SHDN 2 L3 1 LED3H+ CAP1 25 VIN 1 ON OFF LT3496EUFD 2 PVIN U1 TP16 PVIN C13 2.2uF 25V CAP3 C9 1uF 6.3V SW3 GND VIN JP1 LEDs VIN TP15 SW2 VIN 3V-5.5V A PVIN TP2 PVIN C10 4.7uF 63V (OPT) B B * Refer to QSG for PVIN Range. 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 TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 1 CONTRACT NO. APPROVALS DRAWN DATE HELEN 5/05/07 Walker Bai 5/05/07 CHECKED TECHNOLOGY TITLE LT3496EUFD Triple Boost or Buck/Boost LED Driver APPROVED ENGINEER DESIGNER Monday, August 27, 2007 2 SIZE 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 CAGE CODE SCALE: FILENAME: DWG NO REV A DC1288A SHEET 1 OF 1