1 2 3 4 5 6 7 8 Jumpers Select R2 12 Ref. Normal JP8 Short Pin 1,3 Short Pin 2,4 Damped JP9 Short Pin 1,3 Short Pin 2,4 C1 1000pF R4 12 R5 optional AUXOUT+ 1 E1 E16 1 A R6 optional C40 0.01uF FLTCPL R9 10K D1 BAT54C C2 1uF R7 5.1 R8 10 C43 optional 3 2 3 C7 1000pF 1 E17 1 9 E7 1 10 3.3Vout 11 12 E8 1 13 14 R17 47k C26 C27 C18 C28 0.1uF 6800pF 0.1uF 100pF R18 5k C29 C30 6800pF 100pF EXTVCC ITH1 INTVCC SGND PGND 3.3VOUT BG2 ITH2 BOOST2 VOSENSE2 SW2 SENSE2- TG2 SENSE2+ RUN/SS2 5 6 7 8 2 3 4 C17 + 2.2uF C16 22uF 6V 3216 20 1 2 1 1 Q4 IRF7811 4 Vo1+ B 5 6 7 8 5 6 7 8 Q3 IRF7811 4 22 21 J4 D4 MBRS340T3 Q5 optional 4 R13 0.003 + C13 + 470uF 6.3V C14 + 470uF 6.3V C15 470uF 6.3V Vo1- 19 18 Q6 IRF7807 4 C19 0.47uF 17 J3 Q7 IRF7807 4 L2 1.6uH SUMIDA CEPH149-1R6MC 16 R14 0.003 VO2+ Vo2+ 15 1 Q8 IRF7811 4 Q9 IRF7811 4 D5 MBRS340T3 Q10 optional 4 J5 R15 optional + C22 + 470uF 6.3V C23 + 470uF 6.3V C24 470uF 6.3V R20 0 C36 10uF 10V CER Vo2- 1 C C35 10uF 10V CER 1 C20 0.1uF E9 Vin- VO1+ 2 23 C21 1uF C25 1400pF 1 2 3 1 2 3 24 1 2 3 R16 47k BG1 FCB C11 56uF 25V + 1 8 Ith1 STBYMD 25 2 7 VIN C10 56uF 25V J2 1 2 3 6 BOOST1 FREQSET + R12 optional 5 6 7 8 1 VOSENSE1 C44 56uF 25V 1 26 1 2 3 C39 0.01uF E6 SW1 + C12 0.47uF 27 1 2 3 C38 0.01uF SENSE1- 28 J1 C9 1uF 5 6 7 8 5 TG1 5 6 7 8 4 FREQ FLTCPL SENSE1+ 1 2 3 1 B RUN/SS1 L1 1.6uH SUMIDA CEPH149-1R6MC C37 1uF Q2 IRF7807 4 5 6 7 8 3 E5 Q1 IRF7807 4 1 2 3 2 5 6 7 8 JP3 Vin+ 5 6 7 8 1 1 D3 BAT54A 1 2 1 AUXOUT- 1 2 0 U2 LTC1628CG RUN1 D2 BAT54 1 2 3 JP2 JP6 Ith2 0 1 1 E4 INTVCC 0 3 1 1 2 JP1 1 FCB INTVCC C6 1uF 5 6 7 8 2 0 R10 4.3K 1 E3 C8 0.01uF C5 1uF C4 0.1uF 1 2 3 INTVCC R1 1M 3 3 STBYMD C3 1.5uF 35V 3216 3 + 1 3 E2 A 1 SGND C31 1400pF R23 1.58k E10 C32 1000pF 1 C R25 12 C42 1uF SGND J6 R22 12 R26 10 E11 R27 1.58k 1 R28 optional SGND C34 1400pF SGND R31 optional E12 R32 10 1 SENSE2+ C33 1400pF C41 1uF R30 8.3k E13 R11 1.52K 1 SENSE1+ C59 .33uF JP8 1 3 R19 1.52K 2 4 HEADER 2X2 IN1 C60 .33uF JP9 1 3 1 E19 2 4 IN2 HEADER 2X2 1 R21 100 E14 1 E20 0 + C45 + C46 + C47 + C48 + C49 + C50 + C51 RS1 16.7K .1% 1 4 1 1 Vo2+ EXTVcc + C52 + C53 + C54 + C55 + C56 + C57 + C58 RS2 15.2K .1% RS1 IM2 RS2 IN1 6 E18 IN2 5 C61 0.1uF 7 3 2 U1 LTC2920-2CMS8 D 1 2 0 SW2 1 2 LINEAR TECHNOLOGY CORPORATION 1630 McCARTH Y BLVD. MILPITAS, CA95035 (408) 432-1900 (408) 434-0507 FAX Title LTC2920 With Dual DC to DC Converter 0 SW1 Size Document Number 1 1 IM1 3 R3 1M 1 E15 3 3 JP7 1 VCC RUN2 GND 2 D 8 Vo1+ CAPACITORS C45-C58 ARE OPTIONAL INTVcc DC543A Date: Tuesday, June 18, 2002 1 2 3 4 5 6 7 Rev LTC2920-2CMS8/LTC1628CG Sheet 1 of1 8