5 4 3 2 1 REVISION HISTORY ECO __ REV DESCRIPTION 2 APPROVED DATE TOM G. 11-29-12 PRODUCTION D D LTC3621EMS8E U1 2 VIN E1 C1A 8.2uF 25V + C1 10uF 1 VIN 2.7V - 17V 1 2 3 FB 3 6 B MODE/SYNC (Forced Continuous) PS (Pulse-Skip) 1 CFF 22pF C4 1uF R3 619k PGOOD INTVCC MODE/SYNC 7 C2 22uF 5 R4 309k R5 196k R6 137k R7 84.5k JP3 JP4 JP5 JP6 JP7 1.2V 1.8V 2.5V 3.3V 5.0V GND SGND 9 C3 22uF R8 OPT JP8 USER SELECT 8 2 JP2 3 BM (Burst Mode) 1A C 4 R2 100k OPT E2 RUN RUN E8 E7 VOUT VOUT 4.7uH Rpgood 100k INTVCC L1 Rset 619k OFF PGOOD SW JP1 ON C VIN GND B E4 R1 100k OPT E6 GND SYNC E5 GND E3 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. A THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 4 3 APPROVALS PCB DES. TECHNOLOGY HZ 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 17V VIN SYNCHRONOUS STEP-DOWN REGULATOR WITH ULTRA-LOW QUIESCENT CURRENT SIZE IC NO. N/A SCALE = NONE REV. LTC3621EMS8E DEMO CIRCUIT 1863A 2 Thursday, June 13, 2013 DATE: 2 SHEET 1 1 OF 1 A