FAN7554DTF Fairchild Semiconductor, FAN7554DTF Datasheet

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... Over current limit(OCL) • Operating frequency up to 500kHz • 1A totem-pole output current Applications • Off-Line & DC-DC converter ©2003 Fairchild Semiconductor Corporation www.fairchildsemi.com Description The FAN7554 is a fixed frequency current mode PWM controller specially designed for off-line and converter applications with minimal external components. ...

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FAN7554 Internal Block Diagram 3.5V 3.5V Vref Vref 100 uA 100 S/S S 0.3V 0. Vcc Vcc Vcc 5uA 5uA 5uA + + 6V ...

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Temperature Characteristics ( - Parameter Vref temperature stability Fosc temperature stability PIN Array PIN Definitions Pin Number Pin Name S Rt/Ct 5 GND 6 OUT 7 Vcc 8 Vref ...

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FAN7554 Electrical Characteristics ( Vcc=16V, Rt=10k , Ct=3.3nF unless otherwise specified) Parameter < REFERENCE SECTION > Reference output voltage Line regulation Load regulation Short circuit output current < OSCILLATOR SECTION > Oscillation frequency Frequency change with Vcc ...

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Electrical Characteristics ( Vcc=16V, Rt =10k , Ct = 3.3nF unless otherwise specified) Parameter <TOTAL STAND-BY CURRENT SECTION> Start-up current Operating supply current Off State current Note: 1. These parameters, although guaranteed, are not 100% tested in ...

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FAN7554 Typical Perfomance Characteristics [ Rt vs. Freqency ] [ Rt vs. Freqency ] [ Rt vs. Freqency ] [ Rt vs. Freqency ] 10000.0 1000.0 100.0 10.0 1.0 0 Rt[Kohm] Figure 1. Rt vs. Frequency [ Ct ...

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FAN7554 Typical Performance Characteristics Figure 5. Temperature vs. Start-up Current Figure 7. Temperature vs. Reference Voltage Figure 9. Temperature vs. Start Threshold Voltage 7 (Continued) Figure 6. Temperature vs. Operating Supply Current Figure 8. Temperature vs. Oscillation frequency Figure 10. ...

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FAN7554 Operation Description The FAN7554 has all the basic features of the current mode SMPS control IC. Its basic configuration includes the UVLO with 6V hysteresis, a band gap reference, the oscillator that can oscillate up to 500kHz according to ...

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Cs Cs Oscillator As shown in figure14, the oscillator frequency is programmed by values selected for timing components Rt and charged to almost 2.8V through resistor Rt from the 5V reference and discharged to 1. ...

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FAN7554 Feedback As shown in figure16, the internal oscillator clock turns on the MOSFET. The feedback comparator operates to turn it off again, when the MOSFET current reaches a set value proportional to Vfb. The feedback capacitor Cfb is charged ...

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Vfb Vfb 6V 6V Slope (dv/dt) = 5uA / Cfb Slope (dv/dt) = 5uA / Cfb Figure 17-B . Delayed Shutdown & Feedback Waveform Gate Driver The gate drive circuit has the totem-pole output configuration. The ...

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FAN7554 S/S S Cfb Cfb Remote control Remote control Vref Vref S/S S 1.5V 1.5V Vfb Vfb 0.3~3V 0.3~3V 0.3V 0.3V Normal State Normal ...

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Protection Circuits The FAN7554 has many built-in protection circuits that do not need additional components, providing reliability without cost increase. These protection circuits have the auto-restart configuration. In this configuration, the protection circuits reset when Vcc is below UVLO stop ...

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FAN7554 FAN7554 Flyback Converter Demo Circuit (Fsw:100kHz NTC NTC C102 C102 R101 R101 C103 C103 C301 C302 C301 C302 LF101 LF101 C101 C101 TNR TNR FUSE FUSE 8 8 Vref Vcc OUT GND Vref Vcc OUT GND FAN7554 ...

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Part List For FAN7554 Flyback Converter Demo Board Part Value FUSE FUSE 250 2A NTC NTC 5D-11 RESISTOR R101 330k R102 - R103, R104 100k R105 22 R106 4.7k R107 12k R108 10 R109 1k R110 0.5 R201 1k R202 ...

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FAN7554 Transformer Specification Schematic Diagram (Top view Winding ...

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FAN7554 forward converter demo circuit ( fsw:100kHz R105 R105 C102 C102 C301 C302 C301 C302 L101 L101 C103 C103 R106 R106 C101 C101 R101 R101 R102 R102 FUSE FUSE D101 D101 C106 C106 RT101 RT101 Input ...

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FAN7554 Part List For FAN7554 Forward Converter Demo Board Part Value FUSE FUSE 250 2A NTC RT101 DSC 10D-11 RESISTOR R101 330k R102 - R103, R104 56k R105, R106 220k R107 10 R108 20 R109 4.7k R110 1.2k R111 0.5 ...

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Transformer specification Schematic Diagram (Top view) 13, 14 13 32turn Np ; 32turn Np ; 32turn Ns,12 ; 5turn Ns,12 ; 5turn Ns,12 ; 5turn ...

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FAN7554 Mechanical Dimensions Package Symbol Min 0.10 A2 1.25 B 0.35 C 0.19 D 4. 5.79 h 0. aaa - bbb - 20 8-SOP Nom Max - 1.75 ...

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Mechanical Dimensions Package (Continued) 8-DIP Dimensions in millimeters FAN7554 21 ...

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... FAN7554 FAN7554D DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. ...