NCP1379 ON Semiconductor, NCP1379 Datasheet
NCP1379
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NCP1379 Summary of contents
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... Once the timer elapses, the controller stops and enters auto−recovery mode, ensuring a low duty−cycle burst operation. To further improve the safety of the power supply, the NCP1379 features a pin to implement a combined brown−out/overvoltage protection. Particularly well suited for TVs power supply applications, the controller features a low startup voltage allowing the use of an auxiliary power supply to power the device ...
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HV −bulk NCP ZCD / OPP PIN FUNCTION DESCRIPTION Pin N5 Pin Name Function 1 ZCD Zero Crossing Detection Adjust the over power protection 2 FB Feedback pin 3 CS Current sense ...
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INTERNAL CIRCUIT ARCHITECTURE VDD Rpullup FB VDD ICt tpoint − Discharge − Vth ESD DRV 3 ms blanking end / 4 The 40 ms ...
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MAXIMUM RATINGS TABLE(S) Symbol V Maximum Power Supply voltage, VCC pin, continuous voltage CC(MAX) I Maximum current for VCC pin CC(MAX) V Maximum driver pin voltage, DRV pin, continuous voltage DRV(MAX) I Maximum current for DRV pin DRV(MAX) V Maximum ...
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ELECTRICAL CHARACTERISTICS 1 680 pF) For min/max values T CS fault T Symbol Parameter CURRENT COMPARATOR − CURRENT SENSE V Setpoint decrease for V OPP(MAX) ZCD V Threshold for immediate fault ...
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ELECTRICAL CHARACTERISTICS 1 680 pF) For min/max values T CS fault T Symbol Parameter FEEDBACK SECTION − FEEDBACK Valley threshold voltage where 1 valley ends and 2 H2D ...
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T , JUNCTION TEMPERATURE (°C) J Figure 3. V vs. Junction Temperature CC(on) 1.9 1.8 1.7 1.6 1.5 1.4 1.3 −40 − ...
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T , JUNCTION TEMPERATURE (°C) J Figure 9. V vs. Junction Temperature ILIM 1.24 1.23 1.22 1.21 1.20 1.19 1.18 −40 −20 0 ...
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T , JUNCTION TEMPERATURE (°C) J Figure 15. V vs. Junction Temperature ZCD(th) 3.30 3.25 3.20 3.15 3.10 3.05 3.00 −40 − ...
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... Its duration is fixed and equal to 3.8 ms. • Fault input: the NCP1379 and D versions include a brown−out circuit which safely stops the controller in case the input voltage is too low. Restart occurs via a complete startup sequence (latch reset and soft−start). ...
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... NCP1379 has two operating mode: quasi−resonant operation and VCO operation for the frequency foldback. The operating mode is fixed by the FB voltage as portrayed by Figure 22: • Quasi−resonant operation occurs for FB voltage higher than 0.8 V (FB decreasing) or higher than 1.4 V (FB increasing) which correspond to high output power and medium output power ...
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VDD Rpullup FB Vdd ICt Ct Ct setpoint ZCD 10 V Vth ESD DRV Laux As the output load decreases (FB voltage decreases the valleys are incremented from the first to the fourth. When the fourth valley is reached, if ...
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Figure 24. Output Load is Decreased from 2 0 120 Vdc Input Voltage http://onsemi.com 13 www.DataSheet4U.com ...
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Figure 25. Zoom Valley Transition nd rd Figure 26. Zoom Valley Transition http://onsemi.com 14 www.DataSheet4U.com ...
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... To avoid having a too big step in frequency, the time out duration is set to 5.9 ms. Figures 30 and 31 detail the time out operation. The NCP1379 also features an extended time out during the soft−start. Indeed, at startup, the output voltage reflected on the auxiliary winding is low. Because of the voltage drop ...
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− Vth ES D leakage blanking 3 us pulse DRV 100 ns SS end 100 ns Figure 29. Time Out Circuit Figure 30. Time Out Case n51: the 3 http://onsemi.com VDD demag ...
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Figure 31. Time Out Case n52: the 3 VCO operation occurs for FB voltage lower than 0.8 V (FB decreasing), or lower than 1.4 V (FB increasing). This corresponds to low output power. During VCO operation, the switching frequency is ...
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Figure 33 shows the implementation of the fault timer. CS LEB1 R sen se FB/4 ZCD/OPP OPP Soft−start Laux LEB2 V CS(stop) When the current in the MOSFET is higher than “Max Ip” ...
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Figure 34. Auto−Recovery Overload Protection Chronograms The over power compensation is achieved by monitoring the signal on ZCD pin (pin 1). Indeed, a negative voltage applied on this pin directly affects the internal voltage reference setting the maximum peak current ...
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... aux d ZCD ZCD + R V opl ZCD Design example: OVERVOLTAGE PROTECTION / BROWN−OUT NCP1379 combine brown−out and overvoltage detection on the pin Fault. VCC HV−BULK Dz VOVP Rbou OVP/BO 7 VDD IBO Rbol Vclamp Figure 36. Brown−out and Overvoltage Protection ...
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... Figure 37. Operating Chronograms in Case of Overvoltage with NCP1379 Supplied by an Auxiliary Power Supply The following equations show how to calculate the brown−out resistors. First of all, select the bulk voltage value at which the controller must start switching (V bulk(on) voltage for shutdown (V ). Then use the following ...
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... Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. The products described herein (NCP1379), may be covered by one or more of the following U.S. patents; 6,362,067 and 5,073,850. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC) ...