REVISION HISTORY ECO REV DESCRIPTION 1 PRODUCTION DATE APPROVED 11/01/13 TOM G. INTVCC C1 2.2uF 10V R12 OPT D1 CMDSH-3 E1 CLKOUT VIN E3 R11 10 5 6 VIN ON R3 14K R9 150K RUN C9 0.1uF 25V C6 220pF 19 SVIN 20 BOOST 21 INTVCC 22 SW 18 17 16 L1 15 E7 VOUT 2.5V / 3.3V / 5V@5A 1uH 14 C8 100pF 13 R2 10.0K C5 47uF 6.3V 1206 C12 47uF 6.3V 1206 C11 47uF 6.3V OPT E9 R13 R4 3.16K R5 2.21K R6 1.37K R7 OPT. JP1 JP2 JP3 JP4 3.3V 5V OPT. 2.5V 0 R10 100K GND E4 C4 0.1uF 25V 1 3 JP7 ITH C14 + C10 [1] 22uF 22uF 25V 35V OPT C13 22uF 25V OPT C7 10pF 2 OFF SW 7 E8 TRACK RUN TRACK SW C3 22uF 25V PGND DCM (DISCONTINUOUS MODE) JP6 FB C2 22uF 25V E2 4V to 20V GND 25 4 4 SW 3 FCM (FORCED CONTINUOUS MODE) SW 12 2 MODE SW 1 PVIN 11 3 MODE PHMODE VIN C15 0.1uF 25V PVIN PGND 2 RT 10 1 SGND JP5 R15 100K VOUT 100K R1 162K 9 4 PHASE 23 3 PHASE 6 CLKOUT 4 5 PGOOD 3 U1 LTC3605AEUF 8 2 PHASE CLKIN R14 PHMODE 1 2 24 CLKIN Vout SELECT R8 100K PGOOD E5 GND E6 NOTES: [1] C10 IS AN OPTIONAL CAPACITOR. IT IS INSERTED ON THE DC1897A TO DAMPEN THE (POSSIBLE) RINGING VOLTAGE DUE TO THE LONG INPUT LEADS. ON A NORMAL, TYPICAL PCB, WITH SHORT TRACES, THE CAPACITOR IS NOT NEEDED. 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. APPROVALS TECHNOLOGY PCB DES. MI APP ENG. TOM G. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC 5A MONOLITHIC SYNCHRONOUS BUCK REGULATOR SCALE = NONE SIZE IC NO. N/A PCB NO. DATE: LTC3605AEUF DEMO CIRCUIT 1897B 11/07/13 10:52:40 SHEET 1 REV. 1 OF 1