5 4 3 2 1 REVISION HISTORY INTVCCA ECO REV __ VID3 VID2 2 VID4 VID3 H L 2 VID5 VID4 JP6 H L 2 1 JP5 1 JP4 H L VID_EN JP7 H L VID5 APPROVED PRODUCTION MIKE S. DATE 3-5-15 C1 0.1uF 2 3 VID1 2 1 JP3 H L 3 VID2 3 3 VID0 2 1 JP2 H L 3 VID1 3 2 1 1 1 JP1 H L 3 VID0 DESCRIPTION 2 VID_EN D E1 VIN CIN9 +180uF 16V R2 OPT C19 RUN 1 0.22uF 0.22uF R29 R30 OPT OPT 1 2 3 1 2 3 5 5 CIN1 22uF 16V 1210 1 2 3 1 2 3 4 + COUT3 330uF 2.5V + COUT4 330uF 2.5V + R10 10 COUT5 330uF 2.5V R15 C11 4.7uF 16V 0805 27 26 R20 0 24 D1 CMDSH-3 2.2 C8 0.1uF R75 -A 23 Q3 BSC050NE2LS 4 Q11 OPT 1 2 3 4 CIN3 22uF 16V 1210 C20 OPT BSC010NE2LSI 4 5 Q4 BG2 VOUT_SLAVE 0.6V-1.23V/30A 1.5V/30A NOT STUFFED 0.6V-1.23V/120A 4 PHASE CIN4 22uF 16V 1210 SW2 EXTVCCA VOUT2 -B D2 CMDSH-3 TG2 C14 0.1uF VOUT1 4 Q12 OPT R26 3.32K B VOUT2 L2 COUT6 220uF 4V 1206 0.25uH 744301025 R28 665 COUT7 220uF 4V 1206 + COUT8 330uF 2.5V + COUT9 330uF 2.5V + C17 10uF J5 6.3V 0805 COUT10 330uF 2.5V VOUT2- FSW = 400kHz R34 10 E8 E9 1 90 DEG 2 INTVCCA PHASMD R35 100K 3 A 60 DEG 4 PGOOD1 SGND R38 100K PGOOD2 5 R37 10K E13 PGOOD2 NOTES: UNLESS OTHERWISE SPECIFIED EXTVCCA EXTVCCA E14 4 GND VO2_SNS+ VO2_SNS- A CUSTOMER NOTICE E10 E11 E12 R36 30.1K INTVCCA CLKOUTA CLKOUTA INTVCCA PGOOD1 VOUT2+ J6 R31 0 JP9 INTVCCA PHASMD 120 DEG C OPT 5 INTVCCA R33 10 R32 OPT VOUT1+ C5 J3 10uF 0.6V 1.23V / 120A 6.3V 0805 VOUT1J4 0 28 25 CIN2 22uF 16V 1210 COUT2 220uF 4V 1206 1 2 3 29 R9 10 VO1_SNS- R14 5 30 COUT1 220uF 4V 1206 0.25uH 744301025 Q10 OPT 32 31 E5 VOUT1 VIN- VO1_SNS+ E3 R12 665 L1 34 22 CLKOUTA PGOOD2 PGOOD1 PHASMD MODE_PLLIN R27 88.7K 4 C6 0.1uF 33 BSC010NE2LSI 1 2 3 C18 Q2 CLKOUT SW2 PGOOD2 VFB2- PGOOD1 TG2 2 R8 3.32K 4 5 VID_EN CHL_SEL 35 36 VID5 37 VID4 38 VID3 39 VID2 VID1 40 41 42 BOOST2 VFB2+ OPT E7 PLLIN VID0 TK/SS2 VFB2- 3 BURST FCM 43 BG2 MODE_PLLIN PULSE SKIP SNSDC1+ EXTVCC ITH2 21 R25 10K 11 ITH1 20 R24 OPT INTVCC PHASMD OPT VFB1 MODE_PLLIN 9 VIN 12 4 MODE 8 10 C16 VFB2+ 7 DIFFOUT 19 C15 OPT 6 BG1 18 R23 OPT 0 JP8 ITH2 C13 OPT R21 INTVCCA B ITH1 C10 3.3nF 5 VOSNS1- FREQ E6 C9 100pF R18 4.02K C12 OPT R19 OPT R17 10K Q9 OPT SW1 BG1 BOOST1 RUN R22 20K U1 LTC3877EUK VOSNS1+ 17 TK/SS2 4 Q1 BSC050NE2LS 4 CHL_SEL VID_EN 16 TKSS2 VFB1 C7 OPT VID4 SW1 ILIM R16 3 SNS2- C4 0.1uF VID3 TG1 13 R11 OPT VID2 TG1 TK/SS1 SNSA2+ E4 SNSA1+ 15 2 SNSD2+ 1 R13 0 14 TKSS1 ITEMP1 44 SNS1- C VID0 C3 GND 45 C2 VID1 VID5 1 2 3 ITEMP1 5 5 R7 OPT E2 R4 0 2 R6 OPT R5 OPT 0.22uF 0.22uF TK/SS1 GND J2 R3 OPT 1 2 RN1 OPT 1 RN2 OPT D VIN J1 6V - 14V CIN10 +180uF 16V ITEMP1 R1 OPT VIN+ E26 1. ALL RESISTORS ARE 0603. 2. ALL CAPACITORS ARE 0603. 3. INSTALL SHUNTS ON JUMPERS AS SHOWN. 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 HZ APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. M. SHRIVER CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. TECHNOLOGY HIGH CURRENT STEP-DOWN CONVERTER WITH VID PROGRAMMING AND LOW DCR INDUCTORS 2 IC NO. N/A SCALE = NONE 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 SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 3 APPROVALS DATE: MARCH 11, 2014 LTC3877EUK REV. 2 DC2229A-B SHEET 1 1 OF 3 5 4 3 2 1 FAULT_SLAVE INTVCCB INTVCCB VIN FAULT_SLAVE TG3 1 3 4 Q23 2N7002 BOOST1 SW1 R50 CLKOUTA INTVCCB 78.7K R52 EXTVCCB EXTVCCB R54 0 E15 19 18 EXTVCCB 17 C25 4.7uF 0805 OPT 1 2 3 1 2 3 CIN5 22uF 1210 16V 15 TG4 C28 0.1uF 29 + 2.2 Q7 BSC050NE2LSI Q15 OPT CIN7 22uF 1210 16V 4 1 2 3 R56 0 COUT13 330uF 7343 2.5V + COUT14 330uF 7343 2.5V + COUT15 330uF 7343 2.5V VOUT J7 GND J8 CIN8 22uF 1210 16V SW4 R51 OPT VOUT_SLAVE OPT 4 BG4 EXTVCCB BSC010NE2LSI 4 + COUT18 330uF 7343 2.5V + COUT19 330uF 7343 2.5V + COUT20 330uF 7343 2.5V C L4 Q16 OPT 5 Q8 5 INTVCCB CIN6 22uF 1210 16V C24 0.1uF R77 R49 0 16 COUT12 220uF 1206 D4 CMDSH-3 TG1 GND R46 D3 CMDSH-3 INTVCCB COUT16 220uF 1206 4V 0.25uH 744301025 4 1 2 3 9 ITH1 MODE1 21 5 BG1 ISENSE1+ C22 0.1uF COUT11 220uF 1206 0.25uF 744301025 4 R45 0 22 20 Q14 OPT L3 1 2 3 ISENSE1- BSC010NE2LSI Q6 5 5 EXTVCC 4 5 23 SW0 24 TG0 26 25 FAULT1B 27 LOWDCR RUN1 PHASMD 8 C INTVCC BG3 14 7 RUN0 13 C27 0.22uF 6 VIN SYNC R48 OPT BG0 ISENSE0- 12 5 ISENSE0+ ILIM 0 BOOST0 FREQ 4 FAULT0B 28 ITH0 3 MODE0 11 C23 0.22uF RUN_SLAVE 2 10 1 C26 47nF D SW3 U2 LTC3874IUFD#PBF CIN11 +OPT CAP-SVP-F8 R44 0 R43 665 ITH_SLAVE C21 47pF R47 R40 OPT Q13 OPT 4 1 2 3 2 R42 OPT Q5 BSC050NE2LSI VIN R53 665 1 2 3 PGOOD1 D R41 10K 5 R39 0 TKSS1 1 2 3 E25 5 FAULT_SLAVE C29 OPT COUT17 220uF 1206 4V R55 0 R57 OPT JUMPERS TO TIE PHASES TOGETHER B B INTVCCA CHL_SEL R58 0 ITH1 ITH2 R61 0 ITH_SLAVE VOUT1 R59 0 1225 R62 0 VFB2R66 0 TKSS1 R68 0 R65 OPT VFB1 TKSS2 RUN VOUT2 VOUT_SLAVE R60 0 1225 R63 0 1225 VFB2+ R64 0 1225 R67 0 RUN_SLAVE RUN AND RUN _SLAVE DRIVEN WITH DIVIDER ON SHEET3. R69 OPT A A CUSTOMER NOTICE 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 HZ APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. M. SHRIVER CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. TECHNOLOGY TITLE: SCHEMATIC HIGH CURRENT STEP-DOWN CONVERTER WITH VID PROGRAMMING AND LOW DCR INDUCTORS SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 4 3 2 IC NO. N/A SCALE = NONE 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only DATE: MARCH 11, 2014 LTC3877EUK REV. 2 DC2229A-B SHEET 2 1 OF 3 5 4 3 VOUT1 VOUT1 COUT21 OPT 7343 COUT22 OPT 7343 + + COUT23 OPT 7343 + COUT24 OPT 7343 + COUT25 OPT 7343 + Q21 SUM60N02-3m9P TO-263AB COUT26 OPT 7343 PULSE GEN1 COUT28 OPT 7343 + + COUT29 OPT 7343 + COUT30 OPT 7343 + COUT31 OPT 7343 + GND COUT32 OPT 7343 COUT33 OPT 7343 COUT34 OPT 7343 + + COUT35 OPT 7343 + COUT36 OPT 7343 + COUT37 OPT 7343 + COUT38 OPT 7343 E18 Q22 D CIN1-8: Murata GRM32ER61C226KE20L (22uF, 16V, X5R, 1210) CIN9,10: Sanyo 16SVP180MX (180uF, 16V, 30mOhm, 3.0 A RMS) Use Tepro RN5326 for 0 Ohm, 1225 resistor COUT39 OPT 7343 COUT40 OPT 7343 + + COUT41 OPT 7343 + COUT42 OPT 7343 + COUT43 OPT 7343 + VOUT2 VOUT2 J10 SUM60N02-3m9P TO-263AB PULSE GEN2 + COUT3-5,8-10,13-15,18-20: Panasonic EEFSX0E331ER (330uF, 9mOhms, 2.5V, 7343) ISTEP1+ R71 E17 LOAD STEP 0.005 5mV / Amp 1% 2010 ISTEP1E19 DYNAMIC LOAD CIRCUIT FOR VOUT2 VOUT_SLAVE + J9 R70 10k 1% VOUT2 COUT27 OPT 7343 L1- 4: Wurth 744301025 (250nH, DCR=0.32mOhms +/- 7%, Isat = 65A typical, footprint = 11.3mm X 11mm, H = 8.9mm) VOUT1 COUT1,2,6,7,11,12,16,17: Murata GRM31CR60G227M (220uF, 4V, X5R, 1206) E16 D + 1 Notes to PCB designer: DYNAMIC LOAD CIRCUIT FOR VOUT1 OPTIONAL COUT + 2 COUT44 OPT 7343 GND E20 R72 10k 1% E22 R73 0.005 1% 2010 E21 ISTEP2+ LOAD STEP 5mV / Amp E23 ISTEP2- C C OPTIONAL DUAL CHANNEL MOSFETS VIN Q17 BSG0811ND OPT CIN15 OPT 1210 VIN Q18 BSG0811ND OPT SW2 1 SW1 CIN14 OPT 1210 9 CIN13 OPT 1210 9 CIN12 OPT 1210 5 3 6 3 6 2 7 2 7 1 8 1 8 SW2 BG1 TG2 JP10 ON RUN OFF SW3 CIN19 OPT 1210 9 CIN18 OPT 1210 SW4 5 4 5 6 3 6 2 7 2 7 1 8 1 8 BG3 TG4 B VIN Q20 BSG0811ND OPT 3 SW4 R74 0 R78 10.0k 4 10 TG3 Q19 BSG0811ND OPT R82 4.22k R79 OPT 0805 RUN C33 OPT 1206 R80 OPT U3 LT6703IDC-3 1 OUT 2 VS 3 4 +INA GND OPT BG4 R81 OPT C34 OPT 10 SW3 9 CIN17 OPT 1210 RUN C32 OPT BG2 B CIN16 OPT 1210 2 RUN_SLAVE E24 3 4 10 TG1 5 R76 30.1k 10 SW1 4 RUN A A CUSTOMER NOTICE 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 HZ APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. M. SHRIVER CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. TECHNOLOGY TITLE: SCHEMATIC HIGH CURRENT STEP-DOWN CONVERTER WITH VID PROGRAMMING AND LOW DCR INDUCTORS SIZE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 5 4 3 2 IC NO. N/A SCALE = NONE 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only DATE: MARCH 11, 2014 LTC3877EUK REV. 2 DC2229A-B SHEET 3 1 OF 3