5 4 3 2 1 REVISION HISTORY ECO REV DESCRIPTION 2 DATE PRODUTION APPROVED 10/28/11 VIN TAGE B. VIN+ TP3 INTVCC D VAUX INTVCC C9 2.2uF 100V 1210 TP13 TP8 R7 100k C5 2.2uF 100V 1210 C6 2.2uF 100V 1210 C7 OPT 1210 C8 OPT 1210 C29 OPT 1210 + C30 OPT 1210 + CIN1 OPT CIN2 150uF 100V SHT 2 B PGOOD TP4 SGND VOUT1 VOUT TP5 CSS R9 1k 1% 3 4700pF R10 C11 33pF 1k 1% CC1 470pF CC2 0.01uF 5 RC 6 14.7k 1% PLLIN TP10 R21 R24 10K 4 7 8 0 9 D8 BZX84C5V1 VIN R30 64.9k 1206 RUN 1 R15 100k 1% INTVCC R20 100k 1% R14 154k 1% R22 OPT ON 2 VOUT OFF 3 VIN B JP1 R31 12.1K 10 11 12 R13 154k 1% 13 14 R25 0 SS SW1 SENSE1+ TG1 SENSE1- BOOST1 ITH PGND1 SGND BG1 MODE/PLLIN FREQ VIN INTVCC RUN EXTVCC VINSNS BG2 VOUTSNS BOOST2 ILIM TG2 IOSENSE+ SW2 IOSENSE- NC R6 0 R12 27 26 D3 3 22 19 U2 2 C16 INTVCC C14 10uF 1206 D7 DFLS160 3 C24 1uF 17 16 D9 BAS16 TG1 R5 4.7 0805 4 TINP TS BINP TG VCC BOOST BG BG1 D2 1 NC 8 7 6 5 C1 22uF 25V 1210 SiR496DP C12 OPT 1206 SW2 TG2 + R8 10 Q5 SiR496DP D5 B1100 Q4 SiR882DP C VOSTP1 C13 OPT 1206 R29 OPT 1206 VOUT1 C21 OPT 1210 C25 OPT 1210 C27 OPT 1210 R32 0 B R19 OPT CS OPT R18 0.012 2% R26 10 TG1 SW1 R33 OPT EXTVCC BG1 TP12 BG2 R34 R4 100 R3 100 TG2 SW2 R36 OPT CS <------ ------> CUSTOMER NOTICE A CIRCUITRY ON THIS SIDE MUST CONNECT TO SIGNAL GND GROUNDPLANE 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. CIRCUITRY ON THIS SIDE MUST CONNECT TO POWER GND GROUNDPLANE APPROVALS PCB DES. APP ENG. TECHNOLOGY MI TAGE B. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 4 3 2 TG1 SW1 BG1 BG2 SHT 2 TG2 SW2 CS 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 8V - 75V VIN BUCK-BOOST DC/DC CONVERTER SIZE 5 C28 OPT 1210 16V D10 VOUT 4.7uF OPT GND J2 BG2 R1 5.6 0805 VOS+ TP2 L1 SW1 0.22uF 16V VOS+ D6 B240A 19uH C4 12V / 5A MAX 15 C10 R35 OPT J1 + C3 C23 COUT1 COUT2 OPT OPT 330uF 330uF 16V 1210 1210 16V OPT Q3 R28 OPT 1206 VOUT 0.010 2% BAS16 R50 0 C22 0.22uF 18 3 0.1uF C18 0.1uF Q2 SiR870DP LTC4444EMS8E-5 0 OPT 21 20 R11 INTVCC 1 23 3 BAS21 1 D11 24 INTVCC OPT OPT 25 1 C15 1uF 16V 0805 25V 1210 1 2 PGOOD 28 D4 3 OPT VFB 8V GND 1 C2 22uF VAUX U1 LTC3789EGN CF OPT SS C TP7 R2 9 RFB1 113K GND GND TP11 8.06K CF1 8V - 75V J4 VOS+ RFB2 D VIN J3 N/A SCALE = NONE IC NO. LTC3789EGN REV. DEMO CIRCUIT 1878A DATE: Friday, March 02, 2012 SHEET 1 1 2 OF 2 A 5 4 3 AUXILIARY SUPPLY 8V / 50mA VIN D13 R39 BZX84C6V8 100k 1% Q6 1206 MMBTA42-7 D R27 0 D15 VAUX1 VIN GND R41 VAUX1 3 1.58k 1% R37 VFB=0.8V VCC SNS 5 8 4 6 5 2 1 6 3 1 G 7 C19 5 4 D14 1uF 16V R48 CLAMPING SNUBBER/ 400uA SUPPLY BAS21 R47 3 1 ITH/RUN 22.1k 1% 1000pF 2 D 1 4 C17 R38 220k 1206 T1 2 PA0648NL DFLS1100 C20 10uF 10V 1206 Q1 FDC2512 1 U3 LTC3803ES6-5 D12 BAS16 3 R40 OPT R44 100 1 VAUX VIN C31 2 5.6k 1% R43 0.30 1% 1206 14k 1% C R42 10 1% C26 VIN 0.1uF R46 33.2k 1% 33.2k 1% Q9 MMBTA92-7 R45 24.9k 1% C R16 B SHT 1 0 VAUX OPTIONAL BIAS SUPPY U4 LTC3630EMSE SiR496DP SW1 SHT 1 BG1 SHT 1 SW2 BG2 SW2 Q13 SiR496DP BG2 R51 OPT ON VFB RUN R49 0 5 11 R23 OPT C32 OPT VPRG1 OV VPRG2 FBO ISET SS CUSTOMER NOTICE A 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. APP ENG. 5 4 3 2 C34 0.1uF B R55 7 0 R56 6 0 10 C35 47nF TECHNOLOGY MI TAGE B. 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 8V - 75V VIN BUCK-BOOST DC/DC CONVERTER SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. C36 47uF 10V 1210 R54 11.3k 1% APPROVALS PCB DES. C37 OPT 9 OFF 12 CS CS 14 JP2 GND SW1 Q15 SiR882DP BG1 SW GND 1 B BIAS RUN R53 102k 1% TDK VLF10040 1 17 TG2 22uH C33 3 VIN 2.2uF 100V 1210 NC TG2 R52 2M 1% 8 16 GND TG1 TG1 L2 VIN Q8 2 4 NC 13 NC 15 NC VOUT1 VIN 3 Q14 SiR870DP 2 OPTIONAL PARTS R17 OPT 0805 N/A SCALE = NONE IC NO. LTC3789EGN REV. DEMO CIRCUIT 1878A DATE: Friday, March 02, 2012 SHEET 2 1 2 OF 2 A