FA5304S Fuji Electric holdings CO.,Ltd, FA5304S Datasheet

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FA5304AP(S)/FA5305AP(S) Description The FA5304AP(S) and FA5305AP(S) are bipolar ICs for switching power supply control and can directly drive a power MOSFET. These ICs contain many functions in a small 8-pin package. With these ICs, a high-performance power supply can be ...

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FA5304AP(S)/FA5305AP(S) Block diagram FA5304AP(S) FA5305AP(S) 8 Pin Pin Description No. symbol IN (–) 1 Inverting input to error amplifier FB 2 Error amplifier output IS (+) 3 Overcurrent (+) detection GND 4 Ground OUT 5 Output VCC 6 Power supply ...

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Absolute maximum ratings Common to FA5304AP(S) and FA5305AP(S) Item Symbol V Supply voltage CC I Output current O V Error amplifier input IN voltage V Feedback terminal input voltage FB Overcurrent detection V IS terminal input voltage I CS terminal ...

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FA5304AP(S)/FA5305AP(S) Overcurrent limiting circuit section Item Input threshold voltage (Pin 3) Overcurrent detection terminal source current Delay time Latch-mode cutoff circuit section Common to FA5304AP(S) and FA5305AP(S) Item CS terminal sink current Cutoff threshold voltage (Pin 8) Overload cutoff circuit ...

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Description of each circuit 1. Oscillator (See block diagram on page 8.) The oscillator generates a triangular waveform by charging and discharging a capacitor. CT pin voltage oscillates between an upper limit of approx. 3.0V and a lower limit of ...

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FA5304AP(S)/FA5305AP( pin circuit As shown in Figure 5, capacitor C is connected to the CS pin. S When power is turned on, the constant current source (10 A) begins to charge capacitor C . Accordingly, the CS pin ...

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Overload shutdown Figure 9 shows the overload shutdown circuit, and Figure timing chart which illustrates overload shutdown operation.If the output voltage drops due to an overload or short-circuit, the output voltage of the FB pin rises. ...

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FA5304AP(S)/FA5305AP(S) 4.4 Output ON/OFF control The IC can be turned on and off by an external signal applied to the CS pin. Figure 13 shows the external output on/off control circuit, and Figure 14 is the timing chart. The IC ...

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The detection threshold is -0.17v for FA5305A with respect to ground as shown in Figure 17. The operation is similar to that of FA5304A except the threshold is minus voltage compared to that which is plus voltage for FA5304A. Figure ...

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FA5304AP(S)/FA5305AP(S) Design advice 1. Startup circuit It is necessary to start-up IC that the voltage inclination of VCC terminal “dVcc/dt” satisfies the following equation(4). dVcc/dt(V/s)>1.8/(Cs( F)).................................( capacitor connected between CS terminal and GND Note that equation (4) must ...

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Startup circuit connected to rectified line This method is not suitable for FA5304A and FA5305A, especially concerned with re-startup operation just after power- off or startup which AC input voltage goes up slowly. Fig. 21 shows a startup circuit ...

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FA5304AP(S)/FA5305AP(S) 2. Disabling overload shutdown function As shown in Figure 24, connect a 330k to 470k resistor between the CS pin and ground. Then, the CS pin voltage does not rise high enough to reach the reference voltage (7.0V) of ...

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Notice for high frequency operation (1) The final pulse These ICs have the original characteristics about the pulse width at OUT terminal when the IC is stopped by undervoltage lockout, ON/OFF function, or latched mode for overload or overvoltage. ...

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FA5304AP(S)/FA5305AP(S) Characteristic curves ( Oscillation frequency (f ) vs. OSC timing capacitor capacitance ( Output duty cycle vs. FB terminal voltage (V Output duty cycle vs. CS terminal voltage (V 20 Oscillation frequency (f ambient ...

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L-level output voltage (V ) vs. OL output sink current (I ) SINK I [A] SINK IS (–) terminal threshold voltage (V ambient temperature (Ta) FA5305AP(S) IS (–) terminal current (I ) vs. IS(–) IS (–) terminal voltage (V ) ...

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FA5304AP(S)/FA5305AP(S) Error amplifier frequency (f) vs. voltage gain (Av) /phase ( ) Supply current (I ) vs. supply voltage (V CC OFF or OFF latch mode 22 Supply current (I Normal operation ) CC ) vs. supply voltage (V ) ...

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Application circuit Example of FA5304AP(S) application circuit (1) Example of FA5304AP(S) application circuit (2) FA5304AP(S)/FA5305AP(S) 23 ...

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FA5304AP(S)/FA5305AP(S) Example of FA5304AP(S) application circuit (3) Example of FA5305AP(S) application circuit Parts tolerances characteristics are not defined in the circuit design sample shown above. When designing an actual circuit for a product, you must determine parts tolerances and characteristics ...