SC4905A/B High Performance Voltage Mode PWM Controller POWER MANAGEMENT SC4905A/B Isolated 36V TO 72V Vin RCD reset Single switch Forward 12V 50W Output non Synchronous Rectification www.semtech.com SC4905A/B High Performance Voltage Mode PWM Controller POWER MANAGEMENT Start up An input supply voltage for the VIN ranging from 36V to 72V should be applied to CON2 Pin 1 (Positive), and CON2 Pin 4 (Negative). The output voltage of 12V @ 50W (Vout) can be loaded at CON1 Pin 9 (Positive), and CON1 Pin 5 (Negative) and verified at CON1 Pin 8 (Positive), and CON1 Pin 6 (Negative). An ON/OFF (ON open, OFF pulled to input ground) is also provided at CON1 Pin 2. A Jumper/Connector (JP1) is also provided if an external clock is available for synchronization, ground the SYNC pin by shorting the jumper if synchronization is not needed. Before applying the supply voltage, following steps should be performed by the user to analyze the SC4905 evaluation board: 1- Connect the supply to above mentioned terminals. If possible minimize all stray inductance due to long wiring by using twisted wires or short wire connection from the power supply to the terminals. 2- Connect all instruments (DVM, current meters, Loads, oscilloscope probes, etc.). More accurate measurements can be achieved if all stray inductances are minimized. 3- Apply the VIN supply Voltage. Loads and analyze the board. www.semtech.com CON1 9 7 8 3 JP1 A 2.2 R11 C Sense- 5 Vout- U3 C9 0.1u,16V C8 0.1u,16V C7 100u,16V C6 100u,16V 4 1 D12 C24 3 4 PE-68386 C C23 10u,16V CMOSH-3 C20 A C 1u, 16V 1u, 16V D10 C 3 5 C D11 6 1u, 16V D13 C25 A GRM42-2X5R106K16 (Murata) U2 C19 T2 0 SYNC1 220p, 16V Secondary Supply R19 R28 2.2k 1 1.1k R20 39.2k 5 U5 4 C28 C29 0.1u,16V 22n, 16V 8 1 7 2 6 3 5 4 U4 SC4431 R21 3.74k 2 R22 1.1k Vref REF 4.7nF C36 Secondary Supply 22pF C31 R24 MOCD207 C32 3.74k R29 NA 1nF 1 C30 NA C33 680pF R25 100k R26 80.2k 5 R23 5.1k 4 C34 C35 0.1u,16V 22n, 16V U6 SC4431 R27 9.1k Vref 8.25k C27 6 0 2 R18 3 5 500 R17 4 1 CMOSH-3 6 1 1u, 16V D9 C A 7 4 C21 1u, 16V CMOSH-3 ILIM SYNC 1 D8 A RC C22 2.2u, 16V OUT C DMAX 5 Trim D14 B140T A 4 7 Secondary Supply 2 8 C18 1u, 16V CA 9 GND + 5output_half_brick VDD CMOSH-3 CMOSH-3 OUT VFF + R8 TBD SC1301A A FB + 0 CMOSH-3 2k 3 + R12 TBD 2 R16 2 C 499k + .33uF,250V C37 D15 CMOSH-3 R15 Sense+ R9 1N5819HW D7 2 LR2512-01-R025FTR R10 R30 39.2k SC1301A C17 1u, 16V C26 220p, 16V 280k 10 A R14 REF + 0 VDD R13 0 U1 9uH T1 1 8 0 T491X107K016AS 2 J2 VDD SC4905 VDD 1 M1 SUD15N15-95 VDD = 12V J1 REF 1 4 D2 MBRD660CT 2 1 E GRM42-2X5R106K16 (Murata) C15 10u,16V C C14 0.1u,16V D6 ZM4742A 1 10 12 11 C5 100u,16V A A MURA120T3 VDD 3input_half_brick 5 4 3 D3 C Vout+ R2 L1 P1173 D1 MBRD660CT R7 5000 R6 5000 C10 .47uF,100V C B A C13 1u,100V C12 1u,100V 4 FZT853 Q1 C1 470pF,100V R1 10 D5 LS4448 3 R4 500 49.9k GRM44-1X7R105K250AL (Murata) Vin- 2 GRM44-1X7R105K250AL (Murata) ON/OFF R3 1 9 PA0273 R5 C11 10 470pF,100V Vin+ 6 C4 100u,16V C16 10u,16V GRM42-2X5R106K16 (Murata) CON2 A C3 100u,16V C C2 100u,16V 2 C 1 VDD D4 LS4448 3 L2 LQH4N102K04 SEMTECH CORPORATION Title SC4905 Single Switch Forward (RCD Reset) non Synchronous 12V 50W Size Document Number SC4905EVB Date: Thursday, January 24, 2002 Rev 1b Sheet 1 of 1 Revised: Monday, January 28, 2002 SC4905 Single Switch Forward (RCD Reset) non Synchronous 12V 50W Bill Of Materials Item Quantity 1 2 3 4 5 6 7 8 1 1 2 6 5 1 2 3 9 7 10 11 12 13 14 15 16 17 18 19 20 21 22 23 1 2 2 1 1 1 1 1 1 2 1 2 1 1 24 7 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 1 1 1 1 1 1 1 1 1 2 3 1 1 2 2 1 1 1 1 1 1 1 2 2 2 1 1 1 1 1 1 1 1 1 1 2 2 1 Revised: January 28,2002 Reference CON1 CON2 C11,C1 C2,C3,C4,C5,C6,C7 C8,C9,C14,C28,C34 C10 C12,C13 C15,C16,C23 C17,C18,C19,C20,C21,C24, C25 C22 C26,C27 C29,C35 C30 C31 C32 C33 C36 C37 D1,D2 D3 D4,D5 D6 D7 D8,D9,D10,D11,D12,D13, D15 D14 JP1 J1 J2 L1 L2 M1 OUT Q1 R5,R1 R2,R9,R13 R3 R4 R6,R7 R8,R12 R10 R11 R14 R15 R16 R17 R18 R22,R19 R20,R30 R24,R21 R23 R25 R26 R27 R28 R29 SYNC1 T1 T2 U1 U2,U3 U4,U6 U5 Revision: 1b Part 5output_half_brick 3input_half_brick 470pF,100V 100u,16V 0.1u,16V .47uF,100V 1u,100V 10u,16V Manufacturer # Foot Print GHM1545X7R474K250 (Murata) GRM44-1X7R105K250AL (Murata) GRM42-2X5R106K16 (Murata) CON\5OUTPUT_HALF_BRICK CON\3INPUT_HALF_BRICK SM/C_0805 EEJL1CD476R SM/C_0805 SM/C_2220 SM/C_2220 SM/C_1210_GRM 1u, 16V SM/C_0805 2.2u, 16V 220p, 16V 22n, 16V NA 22pF 1nF 680pF 4.7nF .33uF,250V MBRD660CT MURA120T3 LS4448 ZM4742A 1N5819HW SM/C_0805 SM/C_0805 SM/C_0805 SM/C_0805 SM/C_0805 SM/C_0805 SM/C_0805 SM/C_0805 SM/C_2220 DIODE_DPAK SM/DO214AA SM/DO213AC SMB/DO214 SOD123 CMOSH-3 B140T short REF VDD 9uH LQH4N102K04 SUD15N15-95 OUT FZT853 10 0 49.9k 500 5000 TBD LR2512-01-R025FTR 2.2 280k 499k 2k 500 8.25k 1.1k 39.2k 3.74k 5.1k 100k 80.2k 9.1k 2.2k NA SYNC PA0273 PE-68386 SC4905 SC1301A SC4431 MOCD207 GHM1545X7R334K250 (Murata) ZM4742A (Diodes Inc.) CMOSH-3 (Central Semiconductor) P1173.123T (Pulse) LQH4N102K04 (Murata) SUD15N15-95 (Vishay) FZT853 (Zetex) MRC1-100-5000-F-7 MRC1-100-5001-F-7 LR2512-01-R025FTR (IRC) PA0273 (Pulse) PE-68386 (Pulse) SC4905 (Semtech) SC1301A (Semtech) SC4431 (Semtech) MOCD207(Fairchild) SOD523 SM/DO213AC VIA\2P ED5052 ED5052 P1173 SDIP0302 DPAKFET ED5052 SM/SOT223_BCEC SM/R_0805 SM/R_0805 SM/R_1206 SM/R_1210_MCR SM/R_1210_MCR SM/R_0805 ERJL1W SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 SM/R_0805 ED5052 PA0273 PE-68386 MSOP10 SOT23_5PIN SOT23_5PIN SO-8