4 3 2 1 VBUS E1 VBUS 4.35V - 5.5V J1 VBUS 1 D- 2 D+ 3 TP2 ID 4 TP3 GND 5 4 TP1 C1 10uF 6.3V 0603 DD+ U1 C2 10uF VBUCK 6.3V 0603 R1 1.0 5% ID LTC3553EPD VOUT JP1 PBSTAT VBUCK USB Mini-B E2 GND VOUT 20 VBUS VOUT VOUT 18 BVIN 12 C9 2.2uF 6.3V 20% 0402 R2 100k 5% E3 PBSTAT E4 ON 3 4 PBSTAT ON CHRG 14 BAT 17 D2 CHRG C10 10uF 6.3V 0603 R23 1K 5% R24 100K 5% E15 16 C8 100uF 6.3V 1206 20% R20 1.0 5% PROG R3 1.87k 3 SW 1 100mA 500mA JP3 OFF VBUS HPWR JP2 19 VBUCK ON VLDO OPEN LDO_ON E6 R4 10k 5% E7 R5 10k 5% 7 VLDO OPEN R6 510k 5% 5 R7 510k 5% D1 BAT54C OFF 1 JP7 BUCK 1st GND VOUT ON R8 1M 5% OPT R10 1M 5% OPT R25 0 R26 0 OPT E10 11 VINLDO C5 1uF 10V VLDO E9 VLDO 3.3V 150mA R16 20 5% C4 4.7uF 4V SEQ LDO_FB 2 10 C3 1pF 5% OPT 9 E8 GND R15 2.05M R14 649k GND NTC JP8 R12 0 INT R13 EXT 0 Unless noted: Resistors: Ohms, 0402, 1%, 1/16W Capacitors: uF, 0402, 10%, 50V R11 100k 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 CIRUIT 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. 4 VOUT 21 SEQ LDO 1st R18 332k R17 649k STBY NTC 3 VBUCK 1.2V 200mA E11 TP4 LDO_ON R9 100k STBY OPT TP5 15 E13 GND VBUCK 8 VBUS PB2 OFF BAT GND ENTC R19 20 5% C6 10pF 5% LDO 2 JP6 EPL2014-103MLC SUSP VINLDO 6 CHRG BAT VFLOAT = 4.2V 500mA E12 C7 10uF 6.3V 0603 BUCK_FB 1 2 3 L1 10uH HPWR BUCK_ON J2 DF3-3P-2DSA R22 1.0 5% JP5 LDO_ON JP4 BUCK_ON BUCK_ON R21 1.0 5% SUSP VBUCK 2 13 4 E14 PB1 ON E5 PROG E17 VOUT 2.9V - 5.5V 0.5A E16 GND 3 2 CONTRACT NO. APPROVALS TECHNOLOGY DRAWN: G. Barbehenn CHECKED: TITLE: SCHEMATIC SIZE DWG NO. APPROVED: ENGINEER: G. Barbehenn DESIGNER: 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 LTC Confidential-For Customer Use Only LTC3553EPD: Micropower USB Power Manager with Li-Ion Charger, Buck DC/DC, and LDO Regulator X DATE: REV DC1550A Friday, July 24, 2009 A SHEET 1 1 OF 1 1