1 2 3 4 5 6 7 8 REVISION HISTORY ECO REV - 2 DESCRIPTION DATE PRODUCTION APPROVED 11/30/15 DL INTVCC INTVCC MODE E7 CLKIN INTVCC A 2 FCM 3 4 PS/SYNC 5 6 BURST R94 OPT E8 A INTVCC U1 LTC7812EUH R72 0 R92 100K E13 10 9 PLLIN/MODE OV2 6 VFB1 * VBUS VOUT1 R70 R78 0 0 14 VFB2 SGND 21 VSW1 20 S1+ 18 VL1- * R79 49.9K VBUS N/C C43 68pF R35 B ITH1 5 C44 2.2nF VBIAS VBIAS * R102 2010 26 C17 0.1uF ITH1 Q1 BSC093N04LS 15K 1nF C54 ITH2 15 TG1 ITH2 BOOST1 R75 3.6K SW1 BG1 SENSE1+ R34 SS1 0 R37 OPT C47 0.1uF SS2 4 11 BOOST1 7 D1 VL2- S1- S2- TG1 TG2 BG1 BG2 VIN 2010 VBUS_ C51 4.7uF 50V 0805 C59 10uF 50V 1210 C79 OPT 0805 VL1- S1+ E3 VOUT1 VOUT1 RS1 VSW1 1nF S1- EXTVCC EXTVCC B SHT 2 C78 OPT 0805 L1 BG1 4 SS2 C52 0.1uF SHT 2 INTVCC C15 8 * C21 0.1uF CMDSH-4E 1 31 R101 4 R95 TRK/SS1 SENSE1- S2+ SHT 2 J3 0.003 4.7uH COUT4 4.7uF 16V 1206 Q2 BSC093N04LS + COUT5 150uF 16V 7343 + COUT11 150uF 16V 7343 R39 0 VOUT1 C36 OPT 1206 J4 1 2 3 E9 TG1 32 0 10nF TRACK / SS1 2 5 6 7 8 C53 VSW2 23 5 6 7 8 OPT R36 VFB2 OV2 1 2 3 R43 VFB1 SGND C55 OPT 22 FREQ SGND * C49 C62 1nF JP3 FREQ R33 R48 100K 1 R40 0 GND E4 GND 25 J5 RUN2 19 RUN1 BOOST2 28 BOOST2 RUN1 R96 RUN2 SW2 30 SW2 29 TG2 27 BG2 VBUS D2 C4 0.1uF INTVCC 24 RUN2 C60 OPT 1 ON E12 R46 100K OFF SENSE2- C56 C64 4.7uF 3 JP2 C3 OPT 1210 C6 OPT 1210 C5 4.7uF 50V 0805 COUT6 10uF 50V 1210 COUT8 10uF 50V 1210 + COUT1 100uF 50V + COUT2 OPT E6 GND 4 J6 L2 RS2 0.004 1nF 1.0uH R82 OPT RS3 0.004 R80 0 VL2- C63 C GND E1 VIN J1 VSW2 OPT Q22 BSC027N04LS R81 100 CIN2 10uF 50V 1210 4 1 2 3 INTVCC 2 C2 OPT 1210 13 JP1 E11 RUN2 TG2 BG2 S2- SGND VBUS Q21 BSC027N04LS C1 OPT 1210 1 2 3 PGOOD1 SENSE2+ 16 PGND C77 OPT S2+ 12 3 INTVCC 2 OFF 33 3 ON E5 CMDSH-4E 1 C VBUS INTVCC 0 5 6 7 8 RUN1 17 5 6 7 8 E10 RUN1 * PGOOD1 CIN3 10uF 50V 1210 CIN4 10uF 50V 1210 CIN5 OPT 1210 + VIN+ VIN CIN1 33uF 63V J2 ** GND C57 VIN- OPT E2 ** 4~36VIN VBUSFOLLOWSVINWHEN VIN>VBUSSETVOLTAGE DERATEIOUT@VIN<8V D NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS AND CAPACITORS ARE 0603. ASSY VOUT1 ‐A 12V ‐B 12V ‐C 5V R33 35.7K 26.7K 68.1K * R43 499K 499K 357K CUSTOMER NOTICE R78 549K 365K 453K R101 OPT OPT 0 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. R102 0 0 OPT APPROVALS PCB DES. LT APP ENG. DL TECHNOLOGY TITLE: SCHEMATIC WIDE VIN, STEP UP/DOWN POWER SUPPLY SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 1 2 3 4 5 6 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only IC NO. N/A SCALE = NONE DATE: LTC7812EUH DEMO CIRCUIT 2422A SHEET 1 Monday, November 30, 2015 7 8 REV. 2 OF 2 D OPTIONAL DCR SENSING NOTE: WHEN DCR SENSING IS IMPLEMENTED,SHORT RS1 & RS2. REMOVE R30, R29, R80 & R81.STUFF R62 AND R91 WITH 0 OHMS. CALCULATE R51, R53 & C15 AND R89, R90 & C56 PER THE DATA SHEET. ALSO REFER TO QSG FOR EXAMPLE. SHT 1 VSW1 R51 VSW1 S1+ OPT SHT 1 S1+ SHT 1 SHT 1 VSW2 R89 VSW2 OPT R53 OPT R62 S1- S1- S2- VL1- VL1- SHT 1 S2- SHT 1 R90 OPT R91 S2+ SHT 1 S2+ VL2- VL2- SHT 1 OPT OPT VIN L3 EXTVCC J9 VOUT1 E14 EXTVCC R55 OPT SGND C66 OPT 0805 R85 OPT E15 VIN_EMI VIN VBUS VBIAS R93 OPT R86 C61 1uF OPT C65 R100 OPT OPT 0805 C67 OPT 0805 C68 OPT 1210 J10 GND 2.2 VBUS VBUS VSW1 SHT 1 BG1 BG1 4 SHT 1 TG2 SHT 1 VSW2 SHT 1 BG2 VSW2 Q18 OPT CUSTOMER NOTICE BG2 4 APPROVALS LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. TECHNOLOGY LT DL 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only WIDE VIN, STEP UP/DOWN POWER SUPPLY N/A SCALE = NONE Q11 OPT TITLE: SCHEMATIC SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 2 VSW1 1 2 3 SHT 1 4 TG2 1 2 3 C74 OPT 0805 D3 OPT 4 TG1 5 6 7 8 C73 OPT 0805 Q9 OPT 1 2 3 C40 OPT 0805 TG1 5 6 7 8 C39 OPT 0805 SHT 1 1 2 3 VIN 5 6 7 8 Q19 OPT C80 10uF 50V 1210 1 VBUS_ 5 6 7 8 SHT 1 DATE: IC NO. LTC7812EUH DEMO CIRCUIT 2422A Monday, November 30, 2015 SHEET 2 REV. 2 OF 2