5 4 3 R1 OPT 3 1 2 5 6 2 4 2 4 Q7 OPT Q8 OPT 3 3 3 1 TP9 4 Q6 OPT 1 1 VCC C9 C4 0.1uF OPT R5 OPT 2 R17 OPT RC2 0.01uF INTVCC 10K CC4 OPT SS/TRACK CSS 1000pF INTVCC 28 NC TG 27 C6 3 NC SW 26 0.1uF 4 VON SENSE+ 25 5 VRNG NC 24 6 PGOOD NC 23 7 MODE_SYNC NC 22 ON 1 OFF TP8 GND C8 ITH SENSEBGRTN 20 BG 19 R24 R20 R21 DRVCC 18 0 OPT 0 SS_TRACK 12 SGND 13 SDB 14 UVIN INTVCC 17 EXTVCC 16 NDRV 15 Q1 Si7852DP R19 OPT INTVCC 33pF CC2 RC 220pF 90.9K 1% RUV1 VIN R12 0 R18 OPT 33.2K 1% 14K OPT D1 COUT3 10uF B1100 16V C TP5 VOUT VOUT 12V 6A COUT1 270uF + 16V COUT4 10uF 16V + COUT2 270uF 16V OPT + COUT5 + COUT6 OPT C7 R13 R22 0.012 1% 0 TP6 0.1uF R23 0.012 1% GND B R10 R9 OPT TP7 0 Q4 OPT R8 0 C1 TG 4 BG 4 1uF C3 OPT 1 2 3 RF BGRTN 1% Q5 OPT 1 2 3 RFB2 1K 1% 13V - 80V VIN OPT RFB1 OPT OPT VOUT OPT CIN6 1uF R11 OPT VOUT CF CIN5 C5 INTVCC RUV2 100V L1 7.7uH 0.1uF 470K B VIN CIN4 1uF 100V GND C2 CC1 CIN3 1uF 100V 4 BG 2 JP2 CIN2 + 68uF TP2 OPT VFB 11 CIN1 + 68uF 100V 9 PLL_LPF TP1 VIN 4 21 10 VIN 5 6 7 8 TG Q2 Si7852DP 8 3 SHUTDOWN 2 R15 0 BOOST 1 2 3 CC3 ION 1 2 3 JP1 1 5 6 7 8 INTVCC R4 0 3 TP4 VIN 5 6 7 8 MODE/SYNC 1 TP10 VIN 5 6 7 8 4 MODE/SYNC APPROVED U1 LTC3810EG TP3 PULSE SKIP SYNC FORCE CONTINUOUS 10/18/07 D2 BAS19W INTVCC C Q3 ZXMN10A07F 1 2 R2 OPT DATE PROD D R16 24.9K 1% TP11 R6 100K PGOOD R14 OPT CON 100pF 0 DESCRIPTION 4 VIN VIN 3 RON 274K 1% REV VIN VIN R3 VLOGIC 1 ECO INTVCC D 2 REVISION HISTORY This circuit is proprietary to Linear Technology and supplied for use with Linear Technology parts. Customer Notice: Linear Technology has made a best effort to design a circuit that meets customer-supplied specifications; however, it remains the customers 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 Applications Engineering for assistance. CONTRACT NO. A APPROVALS DRAWN MI DATE 08/22/05 CHECKED TECHNOLOGY TITLE STEP-DOWN CONVERTER ENGINEER SIZE DESIGNER CAGE CODE Tuesday, November 06, 2007 SCALE: NONE 4 3 A SCH, LTC3810EG, HIGH EFFICIENCY HIGH VOLTAGE APPROVED 5 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 2 DWG NO REV A DC952A FILENAME: 952A-4.DSN SHEET 1 1 OF 1