NCP1280_05 ONSEMI [ON Semiconductor], NCP1280_05 Datasheet
NCP1280_05
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NCP1280_05 Summary of contents
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NCP1280 Active Clamp Voltage Mode PWM Controller for Off−Line Applications The NCP1280 provides a highly integrated solution for off−line power supplies requiring high−efficiency and low parts count. This voltage mode controller provides control outputs for driving a forward converter primary ...
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V in Disable I START 16 V AUX C AUX + AUX(ON) AUX(OFF) − GND Disable_V − 1.49 V − 3 UV/OV + − + 3.6 V − V REF Disable − ...
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PIN DESCRIPTION Pin Name 1 V This pin is connected to the input voltage of the system. The voltage can be a rectified, filtered line voltage in or output of a power factor correction (PFC) front end. A constant current ...
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ORDERING INFORMATION Device NCP1280DR2 NCP1280DR2G †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. MAXIMUM RATINGS (Note 1) Rating Input Line Voltage Auxiliary Supply Voltage ...
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ELECTRICAL CHARACTERISTICS R = 60.4 kW 1.0 MW, for typical values Characteristic STARTUP CONTROL AND V REGULATOR AUX V Regulation AUX Startup Threshold/V Regulation Peak (V AUX Minimum Operating V Valley Voltage After Turn−On AUX ...
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ELECTRICAL CHARACTERISTICS ( 60.4 kW 1.0 MW, for typical values Characteristic OSCILLATOR Frequency (R = 101 kW − 125 C J Frequency (R ...
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STARTUP THRESHOLD MINIMUM OPERATING 6 THRESHOLD 5 −50 − JUNCTION TEMPERATURE ( C) J Figure 3. Auxiliary Supply Voltage Thresholds versus Junction Temperature 17.0 16.5 16.0 15.5 15.0 ...
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OSC 6 f OSC −50 − JUNCTION TEMPERATURE ( C) J Figure 9. Operating Auxiliary Supply Current versus Junction Temperature 160 150 ...
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T , JUNCTION TEMPERATURE ( C) J Figure 15. Oscillator Frequency versus Junction Temperature −50 −25 ...
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T , JUNCTION TEMPERATURE ( C) J Figure 21. V Input Resistance versus EA Junction Temperature 5.03 5. REF 4. ...
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Measured from 10 AUX 100 C , LOAD CAPACITANCE (pF) L Figure 27. Outputs ...
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I START I START V V AUX in I AUX C AUX Disable Figure 29. Recommended V AUX Power to the controller while operating in the self−bias or DSS mode is provided Therefore, C AUX sized such ...
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V AUX(on) V AUX V AUX(off UV/OV Voltage 0 V Soft−Start Voltage 0 V OUT2 0 V OUT1 0 V Figure 31. Soft−Start Timing Diagram (Using Auxiliary Winding) Feedforward Ramp Generator The NCP1280 incorporates line feedforward ...
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Current Limit The NCP1280 has two overcurrent protection modes, cycle by cycle and cycle skip. It allows the NCP1280 to handle momentary and hard shorts differently for the best tradeoff in performance and safety. The outputs are disabled typically 90 ...
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Maximum Duty Cycle A dedicated internal comparator limits the maximum ON time of OUT1 by comparing the FF Ramp Ramp voltage exceeds V , the output of the Max DC(inv) DC Comparator goes high. This will reset ...
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Oscillator Ramp OUT2 OUT1 Figure 34. Soft−Start Timing Diagram If the soft−start period is too long, V AUX 7 V before the converter output is completely in regulation causing the outputs to be disabled. If the converter output is not ...
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G K −T− SEATING PLANE 0.25 (0.010 NCP1280 PACKAGE DIMENSIONS SO−16 D SUFFIX CASE 751B−05 ISSUE J −B− 0.25 (0.010 ...
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The product described herein (NCP1280) may be covered by one or more U.S. patents. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without ...