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. VID_EN D E1 VIN CIN9 +180uF 16V R2 OPT 2 C19 1 0.22uF 0.22uF R29 R30 OPT OPT 1 2 3 1 2 3 5 5 R9 10 + COUT3 330uF 2.5V + COUT4 330uF 2.5V + R10 10 COUT5 330uF 2.5V VOUT1+ C5 J3 10uF 0.6V 1.23V / 30A 6.3V 0805 VOUT1J4 R15 INTVCCA C11 4.7uF 16V 0805 27 26 D1 CMDSH-3 D2 CMDSH-3 2.2 C8 0.1uF R75 -A VOUT1 VOUT2 VOUT_SLAVE 0.6V-1.23V/30A 1.5V/30A NOT STUFFED -B OPT 0.6V-1.23V/120A 4 PHASE 0 24 TG2 C14 0.1uF 23 Q3 BSC050NE2LS 4 5 R20 Q11 OPT 1 2 3 4 CIN3 22uF 16V 1210 CIN4 22uF 16V 1210 EXTVCCA C20 OPT Q4 BG2 BSC010NE2LSI 4 5 SW2 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 FSW = 400kHz R34 10 E9 1 90 DEG 2 INTVCCA 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 1.5V / 30A VOUT2- E8 PHASMD VOUT2+ J6 R31 0 JP9 INTVCCA PHASMD 120 DEG C 0 R33 10 R32 OPT VO1_SNS- R14 28 25 CIN2 22uF 16V 1210 COUT2 220uF 4V 1206 1 2 3 29 COUT1 220uF 4V 1206 0.25uH 744301025 CIN1 22uF 16V 1210 1 2 3 1 2 3 34 CLKOUTA RUN PGOOD2 R27 PGOOD1 88.7K PHASMD MODE_PLLIN 4 5 30 E5 VOUT1 VIN- VO1_SNS+ E3 R12 665 L1 Q10 OPT 32 CLKOUT 22 PGOOD2 SW2 BSC010NE2LSI 4 5 VID_EN CHL_SEL 35 36 VID5 37 VID4 39 38 VID3 VID1 40 41 42 VFB2- C18 E7 PLLIN VID0 TG2 OPT Q2 C6 0.1uF 33 31 R8 3.32K 4 1 2 3 BURST FCM BOOST2 VFB2+ VFB2- 3 43 TK/SS2 MODE_PLLIN PULSE SKIP SNSDC1+ BG2 PGOOD1 R25 10K 11 ITH2 21 R24 10K EXTVCC 20 15K ITH1 PHASMD 9 INTVCC 12 4 MODE 8 10 C16 VFB2+ 7 VFB1 MODE_PLLIN C15 0.1uF 6 VIN 19 R23 OPT 0 JP8 ITH2 R21 INTVCCA B ITH1 DIFFOUT 18 C9 100pF R18 C10 3.3nF 4.75K C12 47pF R19 C13 2.2nF 10.7K 5 FREQ E6 R17 10K BG1 RUN R22 20K VOSNS1- Q9 OPT SW1 BG1 BOOST1 17 TK/SS2 4 U1 LTC3877EUK OPTIONAL VOSNS1+ 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 TK/SS1 14 TKSS1 ITEMP1 44 SNS1- C VID0 C3 GND 45 C2 VID1 VID2 0.22uF 0.22uF VID5 1 2 3 ITEMP1 5 5 R7 OPT E2 R4 0 2 R6 OPT R5 OPT D GND J2 R3 OPT 1 2 RN1 OPT 1 RN2 OPT VIN+ VIN J1 6V - 14V CIN10 +180uF 16V ITEMP1 R1 OPT 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 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-A SHEET 1 1 OF 3 5 4 3 2 1 FAULT_SLAVE INTVCCB INTVCCB VIN FAULT_SLAVE TG3 1 ISENSE1+ BOOST1 SW1 CLKOUTA R52 EXTVCCB R54 OPT E15 GND C25 OPT 0805 17 R49 16 OPT 5 5 1 2 3 1 2 3 CIN5 OPT 1210 C24 OPT D4 OPT R77 COUT12 OPT 1206 CIN6 OPT 1210 VOUT_SLAVE + OPT C28 OPT 29 TG4 Q15 OPT CIN7 OPT 1210 4 CIN8 OPT 1210 SW4 R51 OPT R56 OPT BG4 EXTVCCB OPT 4 COUT14 OPT 7343 + COUT15 OPT 7343 VOUT_SLAVE+ J7 OPT VOUT_SLAVEOPT + COUT18 OPT 7343 + COUT19 OPT 7343 + COUT20 OPT 7343 C L4 Q16 OPT 5 Q8 + OPT Q7 OPT 4 COUT13 OPT 7343 J8 OPT 15 INTVCCB INTVCCB COUT11 OPT 1206 OPT COUT16 OPT 1206 OPT 4 R53 OPT 1 2 3 9 ITH1 MODE1 EXTVCCB D3 OPT 5 BG1 19 18 Q14 OPT R46 INTVCCB L3 1 2 3 ISENSE1- 20 5 23 SW0 24 EXTVCC R50 OPT EXTVCCB TG0 26 25 FAULT1B 27 LOWDCR RUN1 21 1 2 3 8 C D R45 OPT 22 5 7 INTVCC C22 OPT CIN11 +OPT CAP-SVP-F8 R44 OPT 4 1 2 3 6 RUN0 OPT 4 TG1 C27 OPT VIN PHASMD R48 OPT 4 14 5 BG0 ISENSE0- 13 OPT ISENSE0+ SYNC 4 Q6 BG3 U2 LTC3874IUFD#PBF OPTIONAL BOOST0 12 3 MODE0 ILIM C23 OPT 2 FAULT0B 28 ITH0 1 C26 OPT R40 OPT R43 OPT SW3 C21 OPT RUN_SLAVE 4 VIN Q13 OPT ITH_SLAVE FREQ OPT Q23 Q5 OPT 1 2 3 3 D 11 2 R42 OPT 10 PGOOD1 R47 R41 OPT 5 R39 OPT TKSS1 1 2 3 E25 5 FAULT_SLAVE C29 OPT COUT17 OPT 1206 R55 OPT R57 OPT JUMPERS TO TIE PHASES TOGETHER B B INTVCCA CHL_SEL R58 OPT ITH1 ITH2 R61 OPT ITH_SLAVE VOUT1 R62 OPT VFB2R66 OPT TKSS1 R65 0 VFB1 TKSS2 RUN R68 OPT VOUT2 VOUT_SLAVE R59 OPT R60 OPT 1225 1225 R63 OPT 1225 VFB2+ R64 OPT 1225 R67 OPT RUN_SLAVE 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. HZ VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL 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-A SHEET 2 1 OF 3 5 4 3 DYNAMIC LOAD CIRCUIT FOR VOUT1 OPTIONAL COUT 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 E16 D VOUT2 + COUT27 OPT 7343 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 J9 COUT1,2,6,7: Murata GRM31CR60G227M (220uF, 4V, X5R, 1206) R70 10k 1% ISTEP1+ R71 E17 LOAD STEP 0.002 2mV / Amp 1% 2010 ISTEP1E19 E18 Q22 SUM60N02-3m9P TO-263AB PULSE GEN2 + L1,2: Wurth 744301025 (250nH, DCR=0.32mOhms +/- 7%, Isat = 65A typical, footprint = 11.3mm X 11mm, H = 8.9mm) VOUT1 COUT3-5,8-10: Panasonic EEFSX0E331ER (330uF, 9mOhms, 2.5V, 7343) D CIN1-4: 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 DYNAMIC LOAD CIRCUIT FOR VOUT2 VOUT_SLAVE + 1 Notes to PCB designer: VOUT1 VOUT1 + 2 COUT39 OPT 7343 COUT40 OPT 7343 + + COUT41 OPT 7343 + COUT42 OPT 7343 + COUT43 OPT 7343 + COUT44 OPT 7343 GND E20 R72 10k 1% E22 VOUT2 VOUT2 J10 R73 0.002 1% 2010 ISTEP2+ LOAD STEP 2mV / Amp E21 E23 ISTEP2- C C OPTIONAL DUAL CHANNEL MOSFETS VIN 6 2 7 1 8 SW2 BG1 TG2 VIN R76 34.8k SW2 4 5 3 6 2 7 1 8 1 3 Q18 BSG0811ND OPT JP10 ON RUN OFF RUN 2 RUN C32 OPT BG2 SW3 5 3 6 2 7 1 8 CIN19 OPT 1210 SW4 BG3 TG4 9 CIN18 OPT 1210 10 TG3 4 SW3 R74 0 SW4 4 5 3 6 2 7 1 8 B VIN Q20 BSG0811ND OPT BG4 R79 OPT 0805 RUN C33 OPT 1206 R80 OPT U3 LT6703IDC-3 1 R81 OPT 10 CIN17 OPT 1210 9 CIN16 OPT 1210 R82 0 R78 10.0k B Q19 BSG0811ND OPT RUN_SLAVE E24 3 5 CIN15 OPT 1210 10 TG1 SW1 4 CIN14 OPT 1210 10 SW1 Q17 BSG0811ND OPT 9 CIN13 OPT 1210 9 CIN12 OPT 1210 OUT 2 VS 3 4 +INA GND OPT C34 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. HZ VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL 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-A SHEET 3 1 OF 3