5 4 3 2 1 REVISION HISTORY ECO REV 2 * D ASSY VIN VOUT FREQ L1 C4 -A -B 5V - 26V 15A 10A 500kHZ 0.39uH 2200pF 330kHZ 1.1uH 4700pF 5V - 36V R1 R2 R3 R5 R7 2.15K 73.2K 2.2 1K 1.50K 31.6K 4.7 2K 3.6K 1.62K DESCRIPTION RS2 Q1 Q2 38.3K 0 OHM 57.6K 200 OHM RJK0305DPB BSC093N04LSG RJK0330DPB BSC016N04LSG R9 PRODUCTION APPROVED DATE Johan S 11-xx-09 D E1 VIN+ VIN J1 VIN R15 0 Ohm CIN5 R8 VOUT U1 LTC3775EUD 0 Ohm R1 C4 * * C R5 * 1 R6 10.0K 1% R2 * C2 R4 10.0K 1% 2 3 0.01uF VIN ILIMIT BOOST ILIMITB 100pF RUN TG MODE 15 R9 * B 5 R16 (Opt) SEE TABLE FOR VIN RANGE J2 GND 5 Q1 * 4 E3 VOUT+ VOUT J3 L1 RUN SENSE MODE/SYNC INTVCC 12 5 RS1 10 INTVCC D2 9 FREQ BG SS PGND C6 0.01uF 8 17 C Q3 (Opt) 1 2 3 0 Ohm (Opt) Q2 * Q4 (Opt) VOUT 1.2V * COUT4 100uF 6.3V 4 COUT1 + 470uF 2.5V + COUT2 (Opt) COUT5 + 470uF 2.5V COUT3 1uF 6.3V X5R SEE TABLE FOR OUTPUT CURRENT J4 1 2 3 CMDSH-4E 6 CIN1 100uF 50V VIN- COMP SW 16 * 0.1uF 13 + E2 R3 100pF 14 FB * C3 11 RSNS2 0.010 5% CIN4 (Opt) 1210 CIN3 4.7uF 50V 1210 RS2 *C1 R7 4 0.1uF 50V 0805 C8 RSNS1 0.010 5% CIN2 4.7uF 50V 1210 GND C5 4.7uF 10V 0805 E4 VOUT- B SGND 7 INTVCC E8 SGND RUN E6 E7 SYNC VIN RUN CUSTOMER NOTICE INTVCC MODE A PULSE_SKIP 1 2 SYNC 3 FCC R12 (Opt) VOUT 1k 1 ON R13 LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A APPROVALS CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; PCB DES. RB HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL ENG. Johan S APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. 2 MODE 3 OFF JP2 4 C7 (Opt) CONTRACT NO. R14 (Opt) JP1 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 4 3 2 TECHNOLOGY 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com A Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC HIGH FREQUENCY SYNCHRONOUS STEP-DOWN CONVERTER SIZE NA DATE: IC NO. REV LTC3775EUD DEMO CIRCUIT 1290A Tuesday, December 08, 2009 2 SHEET 1 1 OF 1