A B C D E Vin VIN 4 3 C19 10uF 10V Disable JP1 Spread Spectrum C3 1uF 10V R1 10 C1 22uF 10V R2 1M 2.75V - 8V C2 22uF 10V (Opt.) C20 10uF 10V Gnd 2 Q2B Si7540DP Q2A Si7540DP D1 B320A (Opt.) 4 3 Q5 Si3460DV (Opt.) RUN/SS C15 0.01uF R12 10K TG2 15 22 SW1 SW2 10 19 BG1 BG2 13 PGND 16 18 SSDIS 14 RUN/SS 6 PGOOD 9 TRACK FREQ 3 23 IPRG1 IPRG2 2 24 VFB1 VFB2 7 ITH2 8 ITH1 1 1.8V ( 5A at 5Vin ) D2 B320A (Opt.) 3 C5 47uF 6.3V C8 10uF 6.3V C9 + 150uF 4V (Opt.) C11 470pF C17 (Opt.) R6 5.9K 1% R7 59K 1% C12 100pF R8 15K Gnd E5 PGOOD E7 C21 220pF C13 100pF 3 E3 Q6 Si3460DV (Opt.) FREQ E9 C10 2200pF R4 187K 1% C16 (Opt.) SGnd Vout2 L2 1.5uH IHLP-2525CZ-01 1 2 5 6 TG1 U1 LTC3736EUF-1 R3 11.8K 1% VIN Q4 Si3447BDV (Opt.) 1 2 5 6 17 IPRG1 E10 2 3 1 2 11 4 C4 47uF 6.3V E4 E8 SENSE2+ 3 6 5 2 1 Gnd C7 10uF 6.3V 12 4 Q3 Si3447BDV (Opt.) 6 5 2 1 C6 + 150uF 4V (Opt.) SENSE1+ SGND L1 1.5uH IHLP-2525CZ-01 2.5V ( 5A at 5Vin ) E2 21 PGND2 4 1 Vout1 PGND1 4 2 20 7 8 8 7 5 6 PGND 25 4 6 5 VIN 5 4 Q1A Si7540DP 3 E12 3 1 3 Enable Q1B Si7540DP 4 E1 R5 118K 1% C14 470pF R9 15K R10 59K 1% 2 IPRG2 E11 R13 10K VIN C18 (Opt.) E13 LTC CONFIDENTIAL - FOR CUSTOMER USE ONLY Customer Notice 1 NOTES: 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. UNLESS OTHERWISE SPECIFIED A B C D LINEAR TECHNOLOGY CORPORATION 1630 McCARTHY BLVD. MILPITAS, CA. 95035 408-432-1900 408-434-0507 FAX Title 1 LTC3736EUF-1 2-Phase Dual Synchronous Step-Down Converter with Spread Spectrum and Output Tracking Size Document Number Date: Thursday, September 30, 2004 DEMO 803A Rev LTC3736EUF-1 1 Sheet E of 1