1 2 3 4 5 6 7 8 REVISION HISTORY ECO REV DESCRIPTION APPROVED DATE - 2 PRODUCTION FAB MIKE S. 9/27/10 E1 VO_SNS+ E2 VO_SNS- INTVCC A VOUT 16 2 VOSNS+ TG 15 3 TRKSS SW 14 BG 13 PGND 12 Q1 RJK0305DPB R9 0 21 SGND 11 D1 CMDSH-3 * R12 * L1 Q4 OPT 1 2 3 4 DCR SENSE FILTER / DIVIDER INTVCC J3 COUT1 100uF 6.3V 1206 * COUT2 100uF 6.3V 1206 + COUT3 330uF 2.5V 7343 + COUT4 330uF 2.5V 7343 VIN- VOUT 1.5V / 20A B J4 GND S- ONLY APPLY LOAD FROM J3 TO J4 R20 VOUT J5 1 VOUT EXTVCC COUT5 OPT 1206 5 4 3 2 C10 OPT PLLIN MODE 1 2 3 COUT6 OPT 1206 2 R21 10K E8 GND VOUT * C9 2.2 0.1uF 16V E7 180uF 16V J2 E6 RS1 2512 R13 OPT SVP-F8 VIN 4.5V - 14V + CIN4 R11 10 * Q2 RJK0330DPB 4 C7 4.7uF 16V 0805 Q3 OPT 4 R10 10 S+ + CIN3 SUD50N03-12P LOAD STEP J6 10mV / A 1 5% DUTY CYCLE MAX CCM DCM JP2 E9 1 PULSE GEN R22 10K R23 0.01 2010 5 4 3 2 C Q5 3 R18 137K INTVCC VIN C8 OPT FSW = 300kHz RT 7 R19 OPT JP1 * 6 10 R17 VRNG MODE/PLLIN * 470pF ITH 5 9 1 2 3 ON OFF R15 EXTVCC * 100pF RUN R16 OPT RUN C6 R14 B 4 8 VIN 0.01uF C5 4 C3 0.1uF 16V C4 INTVCC 5 5 BOOST R7 CIN2 22uF 16V 1210 CIN6 22uF 16V 1210 CIN5 OPT 1210 17 18 19 VOSNS- 1 2 3 1 5 R8 20K CIN1 22uF 16V 1210 1 2 3 C2 OPT VIN+ J1 1 2 3 R6 30.1K C1 E3 VIN S+ 5 R5 OPT * PGOOD 0 R3 * * 20 U1 LTC3833EUDC R4 VOUT E5 TRK/SS R2 S- SNS+ R1 100K E4 PGOOD SNS- A NOTES: UNLESS OTHERWISE SPECIFIED C E10 GND 1. ALL RESISTORS ARE IN OHMS, 0603. ALL CAPACITORS ARE IN MICROFARADS, 0603. LOAD STEP CIRCUIT 2. INSTALL SHUNTS ON JUMPERS AS SHOWN. * ASSY -A (DCR SENSE) -B (RSENSE) L1 WURTH 744355047 (0.47uH) COILTRONICS FP1308R3-R44-R (0.44uH) C1 R7 R12 R13 R14 R17 R2,R3 RS1 R15 0.22uF 1000pF 2.15K OPT OPT OPT 0 OPT OPT 0 0 OPT OPT 10 0.000 Ohm 2512, TEPRO RN5326 0.002 Ohm 2512, VISHAY WSL25122L000FEA 13.0K 16.5K CUSTOMER NOTICE D 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. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 1 2 3 4 5 6 APPROVALS TECHNOLOGY PCB DES. NC APP ENG. MIKE S. 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 HIGH EFFICIENCY STEP-DOWN DC-DC CONVERTER SIZE IC NO. N/A SCALE = NONE DATE: REV. LTC3833EUDC DEMO CIRCUIT 1640A-A/B 2 9/27/10 7 SHEET 1 8 OF 1 D