NCP1351ADR2G ON Semiconductor, NCP1351ADR2G Datasheet
NCP1351ADR2G
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NCP1351ADR2G Summary of contents
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NCP1351 Variable Off Time PWM Controller The NCP1351 is a current-mode controller targeting low power off-line flyback Switched Mode Power Supplies (SMPS) where cost is of utmost importance. Based on a fixed peak current technique (quasi-fixed T ), the controller ...
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PIN FUNCTION DESCRIPTION Pin N° Pin Name Function 1 FB Feedback Input 2 Ct Oscillator Frequency 3 CS Current Sense Input 4 GND 5 DRV Driver Output 6 V Supply Input CC 7 Latch Latchoff Input ...
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45k OFFset ICS-dif* ICS-dif* CS ICS-min GND + Vth *(ICS-diff = ICS-max -ICS-min) Figure 2. A Version (Latched Short-Circuit Protection) NCP1351 INTERNAL CIRCUIT ARCHITECTURE + ...
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45k OFFset ICS-dif* ICS-dif* CS ICS-min GND + *(ICS-diff = ICS-max -ICS-min) Vth Figure 3. B Version (Auto-recovery Short-Circuit Protection) NCP1351 ...
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45k OFFset ICS-dif* ICS-dif* CS ICS-min GND + *(ICS-diff = ICS-max -ICS-min) Vth Figure 4. C Version (Latched Short-Circuit Protection) NCP1351 + ...
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45k OFFset ICS-dif* ICS-dif* CS ICS-min GND + *(ICS-diff = ICS-max -ICS-min) Vth Figure 5. D Version (Auto-recovery Short-Circuit Protection) NCP1351 ...
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MAXIMUM RATINGS Symbol V Maximum Supply on V Pin 6 SUPPLY CC I Maximum Current in V Pin 6 SUPPLY CC V Maximum Voltage on DRV Pin 5 DRV I Maximum Current in DRV Pin 5 DRV V Supply Voltage ...
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Electrical Characteristics (For typical values T unless otherwise noted) Symbol SUPPLY SECTION AND V MANAGEMENT CC VCC V Increasing Level at Which Driving Pulses are Authorized ON CC VCC V Decreasing Level at Which Driving Pulses are Stopped STOP CC ...
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The NCP1351 implements a fixed peak current mode technique whose regulation scheme implements a variable switching frequency. As shown on the typical application diagram, the controller is designed to operate with a minimum number of external components. It incorporates the ...
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The Negative Sensing Technique Standard current-mode controllers use the positive sensing technique as portrayed by Figure 6. In this technique, the controller detects a positive voltage drop across the sense resistor, representative of the flowing current. Unfortunately, this solution suffers ...
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Current Sense Pin Figure 8. The Voltage on the Current Sense Pin Below are a few recommendations concerning the wiring and the PCB layout: • A small 22 pF capacitor can be placed between the CS pin and the controller ...
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V Ct Minimum Frequency P out Decreases P out Increases Maximum Frequency Figure 10. The Current Injected into the Feedback Loop Adjusts the Switching Frequency C Voltage t Figure 11. In Light Load Conditions, the Oscillator Further Delays the Restart ...
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Over power protection can be done without power dissipation penalty by arranging components around the auxiliary as suggested by Figure 14. On this schematic, the diode anode swings negative during the on time. This negative level directly depends on the ...
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270p 100n 2. 22pF R offset 3. sense Figure 15. The Feedback Section Inside the NCP1351 The FB pin can actually ...
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At this point, the current is fully compressed and remains frozen. To further decrease the transmitted power, the frequency does not have other choice than going down. CS Current 270 mA FAULT (A, B versions ...
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timer 10m Timer C timer 100nF Reset 2.5k 100n timer 10m Timer C timer 100nF Reset FB ...
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Depending on the design conditions (DCM or CCM), the error flag assertion will correspond to either 50% of the maximum power (full load DCM design value above this number if the converter operates in CCM at full load ...
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ICC1 ICC1 P P out out timer timer startup startup DRV DRV Figure 22. The C Version Latches if the Power Excursion Exceeds 50% of the Maximum Power Too Long ...
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Latch Input The NCP1351 features a patented circuitry which prevents the FB input low impedance before the V reaches the VCC level. As such, the circuit can work primary regulation scheme. Capitalizing on this ...
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Let us round it to 0. Figure 26. Primary Inductance Current Evolution in CCM 2. Calculate the maximum operating duty-cycle for this flyback converter operated in CCM: V out N ...
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HV-Bulk U1B R15 C12 + 3.7k 100mF 3 400V C15 4 22p NCP1351B 100n 2.5k 100n C8 R6 270pF 0.4 Figure 27. The 19 V Adapter Featuring the Elements Calculated Above On this circuit, ...
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Another benefit of the variable frequency lies in the low ripple operation at no-load. This is what confirms Figure 29 200 V/div V out 1.0 mV/div Figure 29. No-Load Output Ripple (V = 230 Vac out ...
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TEMPERATURE (°C) Figure 33. V Level versus Junction CCON Temperature 71 69.5 68 66 TEMPERATURE (°C) Figure 35. I versus Junction CSmin Temperature 517 515 513 ...
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TEMPERATURE (°C) Figure 39. Fault Voltage Variations versus Junction Temperature (A and B Versions) 2.05 2 1.95 1.9 1.85 1.8 1.75 1.7 1.65 - TEMPERATURE (°C) Figure 41. ...
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... ORDERING INFORMATION Device NCP1351ADR2G NCP1351BDR2G NCP1351CDR2G NCP1351DDR2G NCP1351APG NCP1351BPG NCP1351CPG NCP1351DPG †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. NCP1351 Package Type SOIC-8 (Pb-Free) SOIC-8 (Pb-Free) SOIC-8 ...
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... S B 0.25 (0.010 - SEATING PLANE - 0.25 (0.010 *For additional information on our Pb-Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. NCP1351 PACKAGE DIMENSIONS SOIC-8 D SUFFIX CASE 751-07 ISSUE 0.10 (0.004 SOLDERING FOOTPRINT* 1.52 0.060 7.0 4 ...
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... Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada ...