5 4 15 PVin 8 RUN 2 12 Vfb 6 D1 Opt. E8 RFB5 845K 1% COUT1 0.1uF GND JP3 5V RFB2 187K 1% GND E5 2 2 JP2 3.3V RFB1 267K 1% RTR1 255K CFFW 10pF C JP4 Opt. 1 JP1 2.5V EXT SS INT SS TRACK RFB3 115K 1% B RFB4 Opt. RTR2 200K Customer Notice * Capacitor CIN1 Is An Optional Capacitor. It Is Inserted On The DC1445A To Dampen The (Possible) Ringing Voltage Due To The Long Input Leads. On A Normal, Typical PCB, With Short Trace, The Capacitor Is Not Needed. 5 2 RSET 105K LTC CONFIDENTIAL - FOR CUSTOMER USE ONLY A COUT 100uF 6.3V E4 B TRACK VOUT 2.5A Max E3 1 2 4 6 SW 1 1 3 5 13 L1 3.3uH Vishay IHLP-2525CZ-01 1 CSS 0.1uF JP7 TRACK SW CBST 0.22uF 2 Ith RC 4.32K CC 1000pF 3 Track/SS 4 CC1 Opt. 14 DBST CMDSH-3 2 5 CST 1uF 1 Sync/Mode 9 RSD 4.7M Boost 2 1 PGnd JP5 VOUT ENABLE 1 ON 2 OFF 3 C INTVcc 1 PVin PGnd E2 16 PGOOD 17 CIN 22uF 25V CIN2 0.1uF 16V Opt. PGood * CIN1 2.2uF 35V 11 GND U1 LTC3603EMSE SGnd E1 D E7 7 E6 VIN 4V - 15V RPG 100K FC (FORCED CONTINUOUS) BM (BURST MODE) SYNC PS (PULSE-SKIP) PGnd JP6 MODE/SYNC 1 2 3 4 5 6 7 8 Rt SYNC 1 RBM1 845K CBM 0.1uF 10V Opt. D 2 10 RBM2 137K 3 4 LINEAR TECHNOLOGY CORPORATION 1630 McCARTHY BLVD. MILPITAS, CA. 95035 408-432-1900 www.linear.com 408-434-0507 FAX 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. Size Document Number This Circuit Is Proprietary To Linear Technology And Supplied For Use With Linear Technology Parts. Date: Friday, February 13, 2009 3 A LTC3603EMSE Title High Input Voltage 2.5A Monolithic Synchronous Buck Regulator 2 Rev A Demo Circuit 1445A Sheet 1 1 of 1