NCP1207B ON Semiconductor, NCP1207B Datasheet
NCP1207B
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NCP1207B Summary of contents
Page 1
... CISPR-22 EMI starting limit), while the skip adjustment capability lets the user select the frequency at which the burst foldback takes place. For the NCP1207B, the internal timer duration is reduced to 4 allow operation at higher frequencies (up to 200 kHz). The Dynamic Self-Supply (DSS) drastically simplifies the transformer design in avoiding the use of an auxiliary winding to supply the NCP1207A/B ...
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... GND The IC ground 5 Drv Driving pulses 6 V Supplies the High-voltage pin NCP1207A, NCP1207B * + OVP and NCP1207A/B Demag Figure 1. Typical Application Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á ...
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... Minimum Voltage on Pin 8 (HV), Pin 6 (V Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. NCP1207A, NCP1207B VUVLO 4.5/1.5ms Delay ...
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... Low State (Ipin 1 = -2.0 mA) Demag Propagation Delay Internal Input Capacitance at Vpin 1 = 1.0 V Minimum T (Internal Blanking Delay after T OFF Timeout After Last Demag Transition Pin 1 Internal Impedance 1. Max value 0°C. J NCP1207A, NCP1207B (For typical values T = 25°C, for min/max values T J Pin 0° ...
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... Figure 5. VCC Increasing Level at which the Current Source Turns-Off versus Temperature -50 - TEMPERATURE (°C) Figure 7. Internal Startup Current Source versus Temperature CC NCP1207A, NCP1207B 2.3 2.1 1.9 1.7 1.5 1.3 1.1 75 100 125 -50 -25 Figure 4. Internal IC Consumption (1.0 nF Output Load) versus Temperature 10.8 10.3 9.8 9.3 8.8 75 100 125 ...
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... TEMPERATURE (°C) Figure 9. Input Voltage (Vpin1 Decreasing) versus Temperature 8.0 7.8 7.6 7.4 7.2 7.0 6.8 6.6 6.4 6.2 6.0 -50 NCP1207A, NCP1207B 1.20 1.15 1.10 1.05 1.00 0.95 0.90 -50 -25 75 100 125 Figure 10. Maximum Internal Current Setpoint - TEMPERATURE (°C) Figure 11. OVP internal Reference Level versus Temperature http://onsemi.com ...
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... Adjustable skip cycle level: by offering the ability to tailor the level at which the skip cycle takes place, the designer can make sure that the skip operation only NCP1207A, NCP1207B APPLICATION INFORMATION occurs at low peak current. This point guarantees a noise-free operation with cheap transformer. This ...
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... MAINS Figure 13. A simple diode naturally reduces the average voltage on Pin 8 NCP1207A, NCP1207B When using Figure 13 option important to check the absence of any negative ringing that could occur on pin 8. The resistor in series should help to damp any parasitic LC network that would ring when suddenly applying the power to the IC ...
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... Figure 16. When the primary natural ringing becomes too low, the internal timeout together with the sense comparator initiates a new cycle when FB passes the skip level. NCP1207A, NCP1207B current sense comparator permanently resets the latch and the next clock cycle (given by the demagnetization detection) is ignored: we are skipping cycles as shown by Figure 16 ...
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... esd int Figure 18. Internal Pad Implementation An internal timer prevents any re-start within 8.0 ms (NCP1207A) or 4.5 ms (NCP1207B) further to the driver going-low transition. This prevents the switching frequency + 8.0 ms exceed ( avoid false leakage inductance tripping at turn-off. In some cases, the leakage inductance kick is so energetic, that a slight filtering is necessary ...
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... Figure 21. A simple CTN triggers the latchoff as soon as the temperature exceeds a given setpoint NCP1207A, NCP1207B SAMPLING HERE ON/OFF Figure 22. A simple transistor arrangement allows to trigger the latchoff by an external signal Shutting Off the NCP1207A/B Shutdown can easily be implemented through a simple NPN bipolar transistor as depicted by Figure 23 ...
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... R qJA 6.5 mm with 70 mm copper thickness (2 oz). or 6.5 mm NCP1207A, NCP1207B As one can see not recommend using the SO-8 package and the DSS if the part operates at high switching frequencies. In that case, an auxiliary winding is the best solution. ...
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... Let's suppose that this time corresponds to 6.0 ms. Therefore a V fall time could be well appropriated in order CC to not trigger the overload detection circuitry. If the NCP1207A, NCP1207B LATCHOFF PHASE TIME DRIVER PULSES TIME ...
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... P NCP1207A, NCP1207B Current Sense Pin (200 mV/div) This picture explains how the 200 mA internal offset current creates the skip cycle level. goes low ...
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... F -A- NOTE 2 C -T- N SEATING PLANE 0.13 (0.005) M NCP1207A, NCP1207B PACKAGE DIMENSIONS PDIP-8 N SUFFIX CASE 626-05 ISSUE http://onsemi.com 15 NOTES: 1. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 2. PACKAGE CONTOUR OPTIONAL (ROUND OR SQUARE CORNERS). 3. DIMENSIONING AND TOLERANCING PER ANSI Y14 ...
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... G C 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. NCP1207A, NCP1207B PACKAGE DIMENSIONS SOIC-8 NB CASE 751-07 ISSUE 0.10 (0.004 SOLDERING FOOTPRINT* 1 ...
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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 Email: orderlit@onsemi.com NCP1207A, NCP1207B PACKAGE DIMENSIONS SOIC-7 CASE 751U-01 ISSUE D 0.25 (0.010 ...