NEW DATABASE - 350 MILLION DATASHEETS FROM 8500 MANUFACTURERS
NEW DATABASE - 350 MILLION DATASHEETS FROM 8500 MANUFACTURERS
FEB107-001 FAN4803 IEC1000-3-2 265VAC ML4803 AN-42043 AN-42047 250VAC 12VDC - Datasheet Archive
FEB107-001 User's Guide 240W PFC/PWM Combo Evaluation Board Featured Fairchild Product: FAN4803 www.fairchildsemi.com/FEBsupport
www.fairchildsemi.com FEB107-001 FEB107-001 User's Guide 240W PFC/PWM Combo Evaluation Board Featured Fairchild Product: FAN4803 FAN4803 www.fairchildsemi.com/FEBsupport ©2004 Fairchild Semiconductor Page 1 of 14 Rev 2.0 3/2/05 www.fairchildsemi.com Contents 1. General Board Description .3 1.1 The contents of the FEB107-001 FEB107-001 Evaluation Kit .3 1.2 Power Supply Specification Table .3 1.3 FEB107-001 FEB107-001 Schematic .4 2. Test Procedure.5 3. Test Results .5 3.1 Performance Data.5 3.2 Power Ratings .5 4. FEB107-001 FEB107-001 Evaluation Kit Parts List.7 4.1 Vendors for Parts .10 5. Transformer Specification .10 6. Printed Circuit Board .11 6.1 PCB Silkscreen .11 6.2 Layout Considerations .12 7. Featured Products.12 7.1 FAN4803 FAN4803 Description .12 7.1.1 FAN4803 FAN4803 Features.12 8. Resources/References .13 8.1 Application Notes.13 © 2005 Fairchild Semiconductor Page 2 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 1. General Board Description The FEB107-001 FEB107-001 Evaluation Board is a power factor corrected 12V 20A off-line power supply. It is designed to meet IEC1000-3-2 IEC1000-3-2 over the universal input voltage range of 85 to 265VAC 265VAC. The Evaluation Board demonstrates that the FAN4803 FAN4803 can be designed with a low cost single sided PCB at a power level, size, and cost that is compatible with most desk top computer power supply requirements. The FAN4803 FAN4803 is the replacement for the ML4803 ML4803, but either IC will work with this board. 1.1 Contents of FEB107-001 FEB107-001 Evaluation Kit · FEB107-001 FEB107-001 Evaluation Board · FEB107-001 FEB107-001 Evaluation Kit User's Guide · CD ROM containing the following FEB107-001 FEB107-001 Evaluation Kit Users Guide FAN4803 FAN4803 Data Sheet Additional Fairchild data sheets for parts listed on the Bill of Materials Application Note AN-42043 AN-42043 - ML4803 ML4803 240W Off-Line Power Supply with PFC Application Note AN-42047 AN-42047 - Power Factor Correction (PFC) Basics 1.2 Power Supply Specification Table Description Condition Input Voltage (VIN) Min Typ Units 265 85 Max VAC Output Voltage 1 (VOUT) 12.0 V Output Current 1 (I OUT) 20 A Power 120 VAC 290 W Efficiency 120 VAC 81 % Power Factor 120 VAC .98 Figure 1. Photograph of evaluation board © 2005 Fairchild Semiconductor Page 3 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 1.3 FEB107-001 FEB107-001 Schematic LINE C19 4.7nF 250VAC 250VAC F1 J1-1 5A 250V R24 470k 0.5W NEUTRAL L2 TH1 C4 0.47µF 250VAC 250VAC CR1 1000µH 10 5A Q5 BR1 C16 R1 36 J1-2 C1 220µF 450V Q2 C20 4.7nF 250VAC 250VAC 0.01µF R2 L3 36 R22 10k CR5 R3 0.15 3W Q4 CR7 R30 200 R8 36 T2 Q1 3 10 C29 4 1 CR18 51V R23 CR3 0.01µF R38 22 10k C25 0.01µF 500V C18 4.7nF R36 220 T1 12V 2 R13 R4 R26 20k 3W C7 0.1µF 5.62M CR2 C2 CR2 10, 1, 2 1 1 C3 2200µF 1µF L125uH 1k R27 20k 3W R7 10 R12 5.62M 2 3 4 GND Vcc 7 C5 0.01µF R11 150 R32 100 R40 15k R6 1.2k C6 C15 0.015µF C8 0.15µF 36 5 Vdc 12V RET CR10 6 Isense Ilimit Veao R5 8 PWM ML4803 ML4803 R25 390k PFC J2-1 R14 150 2W J2-2 C26 0.01µF 500V Q3 U1 1 CR12 1 7,8,9 C28 C27 1µF 1µF CR11 C10 0.01µF R21 0.01µF CR9 R10 0.75 3W CR4 R9 R31 10 10k R37 1.5k C14 4.7µF 330 5 U3 1 CR8 4 C23 R29 0.01µF 20k CR16 R19 2 C9 R28 L2 1000µH 20k C22 CR15 C13 1µF 10k 1µF 1nF C17 0.1µF R15 9.09k C11 1000µF R173.3k R20 C21 510 1µF 3 2 1 C12 0.1µF R18 1k U2 R16 2.37k . FAN4803 FAN4803 (Detail Below) Figure 2. FEB107-001 FEB107-001 Schematic PFC OUT 1 8 PWM OUT GND 2 7 VCC ISENSE 3 6 ILIMIT VEAO 4 5 VDC TOP VIEW Figure 3. FAN4803 FAN4803 Pin Configuration © 2005 Fairchild Semiconductor Page 4 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 2. Test Procedure Caution The FEB107-001 FEB107-001 Evaluation Board contains voltage potentials capable of causing serious injur y, and components which, if failing, may shatter or explode. Please use extreme caution when operating this board. The use of protective wear is strongly recommended. To safely observe in-circuit waveforms an isolation transformer should be inserted between the AC line and the Board. Do not operate this Board with AC voltages outside the design limits. When replacing components on this Evaluation Board use only those shown in the following par ts list. Use the following procedure to safely operate the power supply. 1. Connect a load (active or resistive) to the output terminals. Set the load to zero amps. 2. Connect a DC voltmeter across the output terminals. 3. Connect an isolated variable AC source (such as a Variac) to the AC input connector (Line and Neutral), with the voltage initially set to zero. 4. Adjust the AC input voltage within the range of 85 to 265VAC 265VAC. 5. The output voltage should read 12VDC 12VDC ±1%. 6. Increase the load to 19.5A. The output, as measured at the output terminals, should regulate within ±0.1% of the nominal reading. The ripple voltage should read less than 30mV RMS. 7. The input power factor should be greater than 0.95. Efficiency should be greater than 80%. 8. Reduce the AC input to zero and verify that the output voltage drops to zero. 3. Test Results 3.1 Performance Data To measure the Evaluation Board performance across the range of permissible input voltages use an isolated Variac or adjustable AC source. A typical FEB107-001 FEB107-001 Evaluation Board will have the performance characteristics shown in Table 1 when operated under the test conditions listed. Table 1: Performance data Input: 85VAC 85VAC 120VAC 120VAC 230VAC 230VAC 265VAC 265VAC Units Efficiency 63 81 68 82 % P. F. 0.99 0.98 0.96 0.97 n.a. Power 50 290 50 290 W 3.2 Power Ratings The FEB107-001 FEB107-001 Evaluation Board is designed to deliver up to 240 Watts at 85VAC 85VAC when used with a properly rated and positioned cooling fan. The power rating without a fan is limited to 150 Watts. A 12V fan can be placed as suggested in Figure 1 and operated from the evaluation board 12V output. © 2005 Fairchild Semiconductor Page 5 of 14 Rev 2.0 March 2005 www.fairchildsemi.com FAN 4.75" sq. x 1.25" thick Air Flow Figure 4: Fan Position © 2005 Fairchild Semiconductor Page 6 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 4. FEB107-001 FEB107-001 Evaluation Kit Parts List Item Description Qty Ref. Vendor Part Number Resistors 1 Resistor 36 Ohm, 5%, 0.25W, Thru Hole 4 R1, R2, R5, R8 Mouser 30BJ250-36 30BJ250-36 / any 2 Resistor 0.15 Ohm, 5%, 3W, Wirewound, Thru Hole 1 R3 Huntington Electric Ohmite ALSR-3J-.15 23JR15 23JR15 3 Resistor 1 K, 5%, 0.25W, Thru Hole 2 R4, R18 Mouser 29SJ250-1k / any 4 Resistor 1.2 Ohm, 5%, 0.25W, Thru Hole 1 R6 Any 5 Resistor 10 Ohm, 5%, 0.25W, Thru Hole 2 R7, R31 Mouser 30BJ250-10 30BJ250-10 / any 6 Resistor 1.5 K, 5%, 0.25W, Thru Hole 1 R9 Mouser 29SJ250-1 29SJ250-1.5k / any 7 Resistor 0.75 Ohm, 5%, 3W, Metal Oxide Film, Thru Hole 1 R10 Panasonic ERX-3SJR75 ERX-3SJR75 8 Resistor 150 Ohm, 5%, 0.25W, Thru Hole 1 R11 Mouser 29SJ250-150 29SJ250-150 / any 9 Resistor 5.62 M, 1%, 0.25W, Thru Hole 2 R12, R13 Dale CMF-55-5 CMF-55-5.62M / or equivalent 10 Resistor 150 Ohm, 5%, 2W, Metal Oxide Film, Thru Hole 1 R14 Yageo Panasonic RSF200JB-150R RSF200JB-150R ERG-2SJ151 ERG-2SJ151 11 Resistor 9.09 K, 1%, 0.25W, Metal Film, Thru Hole 1 R15 Mouser 29MF250-9 29MF250-9.09k / any 12 Resistor 2.37 K, 1%, 0.25W, Metal Film, Thru Hole 1 R16 Mouser 29MF250-2 29MF250-2.37k / any 13 Resistor 3.3 K, 5%, 0.25W, Thru Hole 1 R17 Mouser 29SJ250-3 29SJ250-3.3k / any 14 Resistor 10 K, 5%, 0.25W, Thru Hole 4 R19, R21, R22, R23 Mouser 29SJ250-10k / any 15 Resistor 510 Ohm, 5%, 0.25W, Thru Hole 1 R20 Mouser 29SJ250-510 29SJ250-510 / any 16 Resistor 470 K, 5%, 0.5W, Thru Hole 1 R24 Mouser 29SJ500-470k / any 17 Resistor 390 K, 5%, 0.25W, Thru Hole 1 R25 Mouser 29SJ250-390k / any 18 Resistor 20 K, 5%, 3W, Metal Oxide Film, Thru Hole 2 R26, R27 Panasonic ERG-3SJ203 ERG-3SJ203 19 Resistor 20 K, 5%, 0.25W, Thru Hole 2 R28, R29 Mouser 29SJ25-20k / any 20 Resistor 200 Ohm, 5%, 0.25W, Thru Hole 1 R30 Mouser 29SJ250-200 29SJ250-200 / any 21 Resistor 100 Ohm, 5%, 0.25W, Thru Hole 1 R32 Mouser 29SJ250-100 29SJ250-100 / any 22 Resistor 220 Ohm, 5%, 1W, Metal Oxide Film, Thru Hole 1 R36 Panasonic Yageo ERG-1SJ221 ERG-1SJ221 RSF100JB-220R RSF100JB-220R 23 Resistor 330 Ohm, 5%, 0.25W, Thru Hole 1 R37 Mouser 29SJ250-330 29SJ250-330 / any 24 Resistor 22 Ohm, 5%, 0.25W, Thru Hole 1 R38 Mouser 30BJ250-22 30BJ250-22 / any 25 Resistor 15 K, 5%, 0.25W, Thru Hole 1 R40 Mouser 30BJ250-15k / any 26 Resistor 0 Ohm Jumper 11 JP1 - JP11 DigiKey Yageo 0.0QBK-ND ZO-1/4W-B © 2005 Fairchild Semiconductor Page 7 of 14 Rev 2.0 March 2005 www.fairchildsemi.com FEB107-001 FEB107-001 Evaluation Kit Parts List (continued) Item 27 Description Thermistor 10 Ohm, 5A RMS, Thru Hole - Disc Qty Ref. Vendor Part Number 1 TH1 DigiKey KC006L-ND KC006L-ND ThermoDisc F503EL F503EL THERMOMETRICS, INC. CL-50 CL-50 Capacitors 28 Capacitor 220µF, 20%, 450VDC 450VDC, Electrolytic, Radial 1 C1 Panasonic ECO-S2WB221CA ECO-S2WB221CA 29 Capacitor 2200µF, 20%, 16VDC 16VDC, Electrolytic, Radial 1 C2 Panasonic ECA-1CFQ222 ECA-1CFQ222 30 Capacitor 1µF, 20%, 50VDC 50VDC, Z5U, Radial 5 C3, C6, C9, C21, C22 Panasonic ECU-S1H105MEB ECU-S1H105MEB 31 Capacitor 0.47µF, 20%, 250VDC 250VDC, Film, Radial 1 C4 Panasonic ECQ-E2A474MW ECQ-E2A474MW 32 Capacitor 0.01µF, 20%, 50VDC 50VDC, Z5U, Radial 3 C5, C23, C29 Panasonic ECU-S1H103MEB ECU-S1H103MEB 33 Capacitor 0.1µF, 20%, 50VDC 50VDC, Z5U, Radial 3 C7, C12, C17 Panasonic ECU-S1H104MEB ECU-S1H104MEB 34 Capacitor 0.15µF, 10%, 100VDC 100VDC, X7R, Radial 1 C8 Panasonic ECU-S1H154KBB ECU-S1H154KBB 35 Capacitor 0.01µF, 10%, 50VDC 50VDC, X7R, Radial 1 C10 Panasonic ECU-S1H103KBA ECU-S1H103KBA 36 Capacitor 1000µF, 20%, 25VDC 25VDC, Electrolytic, Radial 1 C11 Panasonic ECA-1EM102 ECA-1EM102 37 Capacitor 1nF, 10%, 100VDC 100VDC, X7R, Radial 1 C13 Panasonic ECU-S1H102KBB ECU-S1H102KBB 38 Capacitor 4.7nF, 10%, 25VDC 25VDC, Film, Radial 1 C14 Panasonic ECS-F1EE475K ECS-F1EE475K 39 Capacitor 15nF, 10%, 100VDC 100VDC, X7R, Radial 1 C15 Panasonic ECU-S1H153KBB ECU-S1H153KBB 40 Capacitor 0.01µF, 10%, 500VDC 500VDC, Ceramic, 3 Radial C16, C25, C26 Panasonic ECK-D2H103KB5 ECK-D2H103KB5 41 Capacitor 4.7nF, 10%, 100VDC 100VDC, X7R, Radial 1 C18 Panasonic ECU-S1H472KBB ECU-S1H472KBB 42 Capacitor 4.7nF, 10%, 250VDC 250VDC, Film, Radial 2 C19, C20 Panasonic ECQ-U2A472MV ECQ-U2A472MV 43 Capacitor 0.01nF, 10%, 25VDC 25VDC, Ceramic, Radial 1 C27 Panasonic ECK-F1E103ZV ECK-F1E103ZV 44 Capacitor 1µF , 25VDC 25VDC, Z5U, 1206 Surface Mount 1 C28 Any Semiconductors 45 Bipolar Transistor PNP, TO-92, FSID: 2N3906 2N3906 1 Q1 Fairchild 2N3906 2N3906 46 MOSFET 0.85Ohm, 500V, TO-220 4 Q2, Q3, Q4, Q5 Fairchild Fairchild HGTP3N60A4D HGTP3N60A4D IRF840B IRF840B 47 Diode Bridge Rectifier, 600V, 4A , KBL, FSID: 1 KBL06 KBL06 BR1 Fairchild KBL06 KBL06 48 Diode HyperFast, 600V, 4A, 20ns, TO-220AC, FSID: ISL9R460P2 ISL9R460P2 CR1 Fairchild ISL9R460P2 ISL9R460P2 © 2005 Fairchild Semiconductor 1 Page 8 of 14 Rev 2.0 March 2005 www.fairchildsemi.com FEB107-001 FEB107-001 Evaluation Kit Parts List (continued) Item Description Qty Ref. Vendor Part Number 49 Diode Schottky, 60V, 30A , TO-247, FSID: MBR3060PT MBR3060PT 1 CR2 Fairchild MBR3060PT MBR3060PT 50 Diode Ultra-Fast, 600V, 1A, 75ns, DO-41 DO-41, FSID: UF4005 UF4005 2 CR3. CR4 Fairchild UF4005 UF4005 51 Diode Zener, 16V, 0.5W , DO-35 DO-35, FSID: 1N5246B 1N5246B 2 CR5, CR9 Fairchild 1N5246B 1N5246B 52 Diode Schottky, 30V, 1A , DO-41 DO-41, FSID: 1N5818 1N5818 4 CR7, CR10, CR11, CR12 Fairchild 1N5818 1N5818 53 Diode Signal, 75V, W , DO-35 DO-35, FSID: 1N4148 1N4148 3 CR8, CR15, CR16 Fairchild 1N4148 1N4148 54 Diode Transorb, 51V, W , DO-15 DO-15, FSID: P6KE51CA P6KE51CA 1 CR18 Fairchild P6KE51CA P6KE51CA 55 IC PFC/PWM Combo, DIP, FSID: FAN4803CP-1 FAN4803CP-1 1 U1 Fairchild FAN4803CP-1 FAN4803CP-1 56 IC Shunt Regulator, TO-92, FSID: TL431CLP TL431CLP 1 U2 Fairchild TL431CLP TL431CLP 57 IC OptoIsolator, DIP-6, FSID: MOC8102 MOC8102 1 U3 Fairchild Fairchild MOC8102 MOC8102 MOC8112 MOC8112 Magnetics 58 Inductor 91µH, MicroMetals Powered Iron 1 L1 Premier Magnetics TSD-1273 TSD-1273 59 Inductor 1.7mH, MicroMetals Powered Iron 1 L2 Premier Magnetics TSD-1274 TSD-1274 60 Ferrite Bead 1 L3 Panasonic EXC-ELSA39 EXC-ELSA39 61 Transformer 100µH 1 T1 XFMRS, Inc. XF4317-00 XF4317-00 62 Transformer - Gate Drive 450µH, 1:1:1 1 T2 Pulse Engineering P0584 P0584 Hardware 63 Fuse 5 A, 250 VAC, 5 x 20 mm 1 F1 Littlefuse DigiKey Series 216 F921-ND F921-ND 64 Hardware Fuse Clips, PC Mount, for 5 x 20 mm fuse 1 F1 (ref.) Littelfuse, etc. 111501 or equiv. 65 Hardware 2-Screw terminal Strip .375" Pitch 1 J2 Tyco Molex/Beau Augat/RDI RDI Augat/RDI 3-1437652-5 71502-C 71502-C LC6-P107-02 LC6-P107-02 6PCV-02 6PCV-02 LC6-P107-02 LC6-P107-02 66 Hardware 0.156" Square 3-Pin Header 1 J1 Molex 26-60-4030 67 Hardware Housing for 0.156" Square 3-Pin Header 1 J1 Molex 09-50-3031 68 Hardware Terminal for 0.156" Square 3-Pin Header 0 J1 (ref) not supplied Molex 08-50-0106 69 Heat Sink .720" High Rise TO-220, AAVID 590102B00150 590102B00150 4 Ref. CR1, CR2, AAVID Q2, Q5 70 Hardware 8-32 Lock Washer 8 Ref. CR1, CR2, Q2, Q5 © 2005 Fairchild Semiconductor Page 9 of 14 590102B00150 590102B00150 Rev 2.0 March 2005 www.fairchildsemi.com FEB107-001 FEB107-001 Evaluation Kit Parts List (continued) Item Description Qty Ref. Vendor Part Number 71 Heat Sink Tube, Berquist SPT400 SPT400 11-25 3 Ref. CR1, Q2, Q5 Berquist SPT400 SPT400 11-25 72 Heat Sink Tube, Berquist SPT400 SPT400 13.5-25 1 Ref. CR2 Berquist SPT400 SPT400 13.5-25 73 Heat Sink Twisted Fin, TO-220, AAVID 593002B03400 593002B03400 2 Ref. Q3, Q4 AAVID 593002B03400 593002B03400 74 Hardware Heatsink Assembly kit, Thermalloy 2 48805 Ref. Q3, Q4 Thermalloy 48805 75 Hardware 4-40 x .25" screws 8 76 Hardware Ground Plate, Paradigm Metals PLATE, ref: P.O. 28678 0 Not supplied Paradigm Metals PLATE, ref: P.O. 28678 77 Hardware Round Aluminum 4-40 threaded 0.375" spacers 4 Digikey J170-ND J170-ND 78 Hardware 6-32 X 0.25" Screw 8 79 PCB FAN4803EVAL FAN4803EVAL P.C. Board Rev B 1 Fairchild Rev. B 80 Hardware 4-40 x .375" Philips screws 8 Ref. Q3, Q4 4.1 Vendors for parts The components listed in the parts list are available from the following list: Future Active Incorporated Digi-Key Corporation Mouser Electronics Premier Magnetics http://www.premiermag.com/ Xfmrs. Inc. http://www.xfmrs.com/index.html Pulse Engineering http://www.pulseeng.com/default.cfm (800) 723-5817 (800) 344-4539 (800) 346-6873 (949) 452-0511 (317) 834-1066 (619) 674-8100 5. Transformer Specification FEB107-001 FEB107-001 T1 Forward Transformer Spec. 1. SCHEMATIC DIAGRAM. (TOP VIEW) 7 Secondary 1 Primary 2 Outside 10 8 Primary Secondary 5 Bias 6 Bias Secondary 11 9 Bobbin Primary A Secondary Inside 12 © 2005 Fairchild Semiconductor Page 10 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 2. WINDING SPECIFICATION PIN WIRE TURNS Primary A 21 28AWG 28AWG 84 Secondary 7,8,9 10,11,12 3×1 7 Bias 56 28AWG 28AWG 4 Primary B 21 28AWG 28AWG 84 3. CORE & BOBBIN CORE: EE4035 EE4035 BOBBIN: EE4035 EE4035 6. Printed Circuit Board The PCB is a single layer board constructed of FR4. 6.1 PCB Silkscreen Figure 3: FEB107-001 FEB107-001 PCB top silkscreen © 2005 Fairchild Semiconductor Page 11 of 14 Rev 2.0 March 2005 www.fairchildsemi.com 6.2 Layout considerations The FEB107-001 FEB107-001 Evaluation board contains high impedance, low level signals and low impedance, high level circuits. Consequently, it requires extra care in component placement, grounding and PC trace routing. In order to shield low level circuits from the high level signals, the control circuits are placed in surface mount form on the bottom side of the board. Since the current sense for the FAN4803 FAN4803 is not differential, care must be taken to prevent large di/dt across the PCB trace joining the output capacitor and the current sense resistor. As the best place to reference the IC is at the output capacitor return potential (the most stable potential), the difference between this potential and the current sense resistor return potential must be kept to a minimum. This is accomplished by "starring" all 400V return connections to the output capacitor, and/or "starring" very low inductive/resistive paths from all power devices to the output capacitor return. Output common mode capacitors C23 and C26, along with a ground plane, have been added as a low impedance path for shunting output common mode currents back to the source through C20 and C19. Although it is not absolutely necessary for a functioning FEB107-001 FEB107-001 Evaluation Board, it does help to reduce high frequency output noise and improve output voltage regulation. The following list some general layout guidelines. A. Bypass the VCC pin directly to the IC ground pin with a 1µF ceramic capacitor, located as close as possible to the IC. B. Return all compensation components directly to the IC ground pin, keeping the lead lengths as short as possible. C. Make sure that low level noise-free returns do not share return paths with high level, or noisy signals, e.g., gate drive. D. Isolate and or shield rapidly changing high voltage waveforms from sensitive, high impedance circuits, such as the timing capacitor, PFC current sense input, error amplifier input/output, etc. E. "Star" connect all power return paths to the boost output capacitor C1. 7. Featured Products 7.1 FAN4803 FAN4803 Description The FAN4803 FAN4803 is a space-saving controller for power factor corrected, switched mode power supplies that offers very low start-up and operating currents. Power Factor Correction (PFC) offers the use of smaller, lower cost bulk capacitors, reduces power line loading and stress on the switching FETs, and results in a power supply fully compliant to IEC1000-3-2 IEC1000-3-2 specifications. The FAN4803 FAN4803 includes circuits for the implementation of a leading edge, average current "boost" type PFC and a trailing edge, PWM. The FAN4803-1 FAN4803-1's PFC and PWM operate at the same frequency, 67kHz. The PFC frequency of the FAN48032 FAN48032 is automatically set at half that of the 134kHz PWM. This higher frequency allows the user to design with smaller PWM components while maintaining the optimum operating frequency for the PFC. An overvoltage comparator shuts down the PFC section in the event of a sudden decrease in load. The PFC section also includes peak current limiting for enhanced system reliability. 7.1.1 FAN4803 FAN4803 Features · · · · · · Internally synchronized PFC and PWM in one 8-pin IC Patented one-pin voltage error amplifier with advanced input current shaping technique Peak or average current, continuous boost, leading edge PFC (Input Current Shaping Technology) High efficiency trailing-edge current mode PWM Low supply currents; start-up: 150µA typ., operating: 2mA typ. Synchronized leading and trailing edge modulation © 2005 Fairchild Semiconductor Page 12 of 14 Rev 2.0 March 2005 www.fairchildsemi.com · Reduces ripple current in the storage capacitor between the PFC and PWM sections · Overvoltage, UVLO, and brownout protection · PFC VCCOVP with PFC Soft Start 8. Resources/References 8.1 Application Notes Application Note AN-42043 AN-42043 - ML4803 ML4803 240W Off-Line Power Supply with PFC Application Note AN-42047 AN-42047 - Power Factor Correction (PFC) Basics © 2005 Fairchild Semiconductor Page 13 of 14 Rev 2.0 March 2005 www.fairchildsemi.com © 2005 Fairchild Semiconductor Page 14 of 14 Rev 2.0 March 2005