NCP1072 ONSEMI [ON Semiconductor], NCP1072 Datasheet

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... The NCP1072/NCP1075 products integrate a fixed frequency current mode controller with a 700 V MOSFET. Available in a PDIP−7 or SOT−223 package, the NCP1072/5 offer a high level of integration, including soft−start, frequency−jittering, short−circuit protection, skip−cycle, a maximum peak current set point, ramp compensation, and a Dynamic Self− ...

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... GND 7 GND FB DRAIN 6 DRAIN Figure 1. Pin Connections 230 Vac 50° kHz, circuit mounted on minimum copper area as recommended. sw NCP1072 11 250 65 100 130 PDIP / SOT223 Figure 2. Typical Application Example http://onsemi.com GND 2 3 (Top View) SOT−223 100 – 250 Vac ...

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PIN FUNCTION DESCRIPTION Pin N5 Pin Name 1 V Powers the internal circuitry GND The IC Ground 4 FB Feedback signal input 5 Drain Drain connection 6 7 GND The IC Ground 8 GND The IC ...

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MAXIMUM RATINGS TABLE Symbol V Power Supply Voltage on all pins, except Pin 5(Drain) CC BVdss Drain voltage I Drain Current Peak during Transformer Saturation DS(PK) I_V Maximum Current into Pin 1 when Activating the 8.2 V Active Clamp CC ...

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... I FB current for which Fault is detected FBfault I FB current for which internal current set−point is 100% (I FB100 current for which internal current setpoint (NCP1072) or FBfreeze 158 mA (NCP1075) Equivalent pull−up voltage in linear regulation range V FB(REF) (Guaranteed by design) Equivalent feedback resistor in linear regulation range ...

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... S The internal ramp compensation in NCP1072 (100 kHz version) a(100) S The internal ramp compensation in NCP1075 (100 kHz version) a(100) S The internal ramp compensation in NCP1072 (130 kHz version) (Note 4) a(130) S The internal ramp compensation in NCP1075 (130 kHz version) (Note 4) a(130) PROTECTIONS t Fault validation further to error flag assertion ...

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TEMPERATURE (°C) Figure 4. V vs. Temperature CC(on) 6.6 6.5 6.4 6.3 6.2 6.1 −50 − TEMPERATURE (°C) Figure 6. V vs. Temperature CC(off) 0.80 0.75 ...

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... Figure 13 100 kHz kHz 100 125 −50 −25 Figure 15. D http://onsemi.com 100 125 vs. Temperature start1 NCP1075 NCP1072 100 125 TEMPERATURE (°C) vs. Temperature IPK( 100 125 TEMPERATURE (°C) vs. Temperature (max) ...

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TEMPERATURE (°C) Figure 16. F vs. Temperature min 510 490 470 450 430 410 390 370 350 −50 − TEMPERATURE (°C) t vs. ...

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... Introduction The NCP1072/NCP1075 offers a complete current−mode control solution. The component integrates everything needed to build a rugged and low−cost Switch−Mode Power Supply (SMPS) featuring low standby power. The Quick Selection Table on page 2 details the differences between references, mainly peak current setpoints and operating frequency. • ...

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Startup Sequence When the power supply is first powered from the mains outlet, the internal current source (typically 8.0 mA) is biased and charges up the V capacitor from the drain pin. CC Once the voltage on this V capacitor ...

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Figure 22. The Charge/Discharge Cycle Over one can see, even if there is auxiliary winding to provide energy for happens that the device is still CC biased by DSS during start−up time ...

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Fault Condition – Output Short−Circuit As soon as V reaches V CC CC(on) internally enabled. If everything is correct, the auxiliary winding increases the voltage on the V voltage rises. During the start−sequence, the controller smoothly ramps up the peak ...

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nom CC(clamp) stby limit I trip Where the auxiliary voltage at nominal load nom V is the auxiliary voltage when standby is entered stby I is the current corresponding to the ...

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Fine tuning of R thus requires a few iterations and limit experiments on a breadboard to check the auxiliary voltage Figure 25. The Burst Frequency Becomes so ...

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Improving the precision in auto−recovery OVP Given the OVP variations the internal trip current dispersion incur sometimes more interesting to explore a different solution, improving the situation to the cost of a minimal amount of surrounding elements. Figure ...

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... The internal peak current set−point is following the feedback current information until its level reaches I Below this value, the peak current setpoint is frozen (NCP1072) or 168 mA (NCP1075). The only way to further reduce the transmitted power is to diminish the operating frequency down to F value is reached at a feedback current level of I (100 mA typically) ...

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Figure 31. Ipk Set−point is Frozen at Lower Power Demand. Feedback and Skip Figure 32 depicts the relationship between feedback voltage and current. The feedback pin operates linearly as the absolute value of feedback current (I Figure 33 depicts the ...

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... Set−point Varies with Power Switch On Time, Which is Caused by the Ramp Compensation PK Figure 33. Skip Cycle Schematic Here we got a table of the ramp compensation, the initial current set point, and the final current set−point of different versions of switcher. NCP1072 65 kHz 100 kHz 130 kHz 4.2 kA/s 6.5 kA/s 8 ...

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Design Procedure The design of an SMPS around a monolithic device does not differ from that of a standard circuit using a controller and a MOSFET. However, one needs to be aware of certain characteristics specific of monolithic devices. Let ...

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We will see how to calculate it later on. 4. Calculate the maximum operating duty−cycle for this flyback converter operated in CCM out max ...

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Figure 37. Different Options to Clamp the Leakage Spike Figure 37a: the simple capacitor limits the voltage according to The lateral MOSFET body−diode shall never be forward biased, either during start−up (because of a large leakage inductance ...

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Figure 38. A Possible PCB Arrangement to Reduce the Thermal Resistance Junction−to−Ambient NCP1075 based Flyback Converter Featuring Low Standby Power Figure 40 depicts a typical application showing a NCP1075−65 kHz operating converter. To ...

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... Figure 40 – 0.85 A Universal Mains Power Supply ORDERING INFORMATION Device Frequency NCP1072STAT3G 65 kHz NCP1072STBT3G 100 kHz NCP1072P65G 65 kHz NCP1072P100G 100 kHz NCP1075STAT3G 65 kHz NCP1075STBT3G 100 kHz NCP1075P65G 65 kHz NCP1075P100G 100 kHz †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 ...

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0.08 (0003) A1 2.0 0.079 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. ...

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... C 3.94 4.45 0.155 0.175 D 0.38 0.51 0.015 0.020 F 1.02 1.78 0.040 0.070 G 2.54 BSC 0.100 BSC H 0.76 1.27 0.030 0.050 J 0.20 0.30 0.008 0.012 K 2.92 3.43 0.115 0.135 L 7.62 BSC 0.300 BSC --- 10 --- 10 N 0.76 1.01 0.030 0.040 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1072/D ...