FA13842P Fujitsu, FA13842P Datasheet
FA13842P
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FA13842P Summary of contents
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... When our ICs are applied to a power supply circuit designed for other manufactures' 384X series, the characteristics and safety features of the power supply must be checked. Types of FA1384X series Type UVLO Start threshold Stop threshold cycle FA13842P 16. FA13842N FA13843P 9. FA13843N FA13844P 16.5V 1V ...
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FA13842, 13843, 13844, 13845 Block diagram FA13842, 13843 VCC 7 UVLO VCC 5V REF 30V ENB 2.5V UVLO RT/CT OSC 4 ER AMP COMP ISNS 3 5V Controlled block FA13844, 13845 VCC ...
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Recommended operating conditions Item Symbol Supply voltage V CC Oscillation timing capacitor C T Oscillation timing resistor R T Oscillation frequency f OSC Electrical characteristics (Vcc=15V, R Reference voltage section Item Symbol Reference voltage V REF Line regulation L INE ...
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FA13842, 13843, 13844, 13845 Output section Item Symbol High-level output V OH Low-level output V OL Rise time tr Fall time tf Under-voltage lockout section Item Symbol Start threshold Min. operating voltage V TH OFF Hysteresis V ...
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Characteristic curves (Ta=25˚C) Timing resistance vs. oscillation frequency FA13842, FA13843 100 2.2nF 470pF C =10nF 15V CC Ta= 25˚ Oscillation frequency (kHz) Timing resistance vs. oscillation frequency FA13844, FA13845 100 470pF 2.2nF C ...
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FA13842, 13843, 13844, 13845 ISNS threshold voltage vs. COMP voltage 1200 V = 15V CC FB= 0V 1000 OUT= off 800 600 400 200 COMP voltage (V) COMP to ISNS offset voltage vs. temperature 2.5 ...
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VCC supply current vs. VCC supply voltage 10k 3.3nF 7 T OUT= No load VCC voltage (V) Output waveform Vcc=15V, OUT CL=1nF, Ta=25˚C V ...
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FA13842, 13843, 13844, 13845 Description of each circuit 1. Oscillator The oscillation frequency is determined by timing resistance R and timing capacitor C , which are connected to RT/CT T terminal charged to about 3V through R T ...
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Output stage An output stage of CMOS inverter composition is incorporated, thereby making it possible to fully swing the gate voltage of a power MOSFET to the The output stage provides a source current of 400mA ...
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FA13842, 13843, 13844, 13845 Latched shutdown 3. A typical circuit for latched shutdown is shown in Fig. 8. The voltage of the OUT terminal is kept low if the voltage of the COMP terminal is low. The voltage of the ...
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The method of detecting an overvoltage (detection on primary side) A typical latched shutdown circuit to protect against overvoltages detected on the primary side is shown in Fig. 11. When the secondary voltage increases in the flyback circuit, the ...
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FA13842, 13843, 13844, 13845 4. Soft start A soft-start circuit is shown in Fig. 15. An aproximate soft-start time is determined with the following calculation. This soft-start time is defined as the time the ISNS terminal threshold voltage increases from ...
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Feedback circuit 7-1 A method that does not use an internal ER AMP A method that does not use an internal ER AMP is shown in Fig. 18. Connect the FB terminal to GND and connect an optocoupler to ...
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FA13842, 13843, 13844, 13845 Fig. 22 illustrates a case when the inductor current variation i ’ smaller than i at t0. In this case, inductor current L L variations gradually converges and the inductor current becomes stable. ...
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Application circuit AC80~264V ~ R1 560k FA13842 R VCC T 7 8.2k UVLO 30V UVLO COMP 1 RT/ C11 1000pF 2200pF 2 1R PC2 R19 ISNS 1k 3 R18 C10 1k 100pF ...