NCP1217A ON Semiconductor, NCP1217A Datasheet
NCP1217A
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NCP1217A Summary of contents
Page 1
... Built−in Internal Ramp Compensation • Auto−Recovery Internal Output Short−Circuit Protection • Internal 1.0 ms Soft−Start (NCP1217A Only) • Limited Duty−Cycle to 50% (NCP1217A Only) • Full Latchoff if Adjustment Pin is Brought High • Extremely Low No−Load Standby Power • Internal Temperature Shutdown • ...
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... Sets the peak current setpoint 3 CS Current sense input 4 Gnd The IC ground 5 Drv Driving pulses 6 V Supplies the Ensures a clean and lossless startup sequence NCP1217, NCP1217A See Application Section + NCP1217 Adj Gnd Drv 4 ...
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... Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. NCP1217, NCP1217A Latchoff Comparator + − ...
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... Leading Edge Blanking Duration INTERNAL OSCILLATOR ( Pin 5 Loaded by 1.0 kW) CC Oscillation Frequency, 65 kHz Version Oscillation Frequency, 100 kHz Version Oscillation Frequency, 133 kHz Version Maximum Duty−Cycle, NCP1217 Maximum Duty−Cycle, NCP1217A 1. Maximum Value @ T = 0° Minimum Value @ T = 125°C. J NCP1217, NCP1217A (For typical values T = 25° ...
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... TEMPERATURE (°C) Figure 3. High Voltage Pin Leakage Current vs. Temperature 9.0 8.5 8.0 7.5 7.0 − TEMPERATURE (°C) Figure 5. VCC vs. Temperature MIN NCP1217, NCP1217A (For typical values T = 25°C, for min/max values T J Pin Symbol 2 Rup − Iratio 1 Vskip 1 Zout 3 Vramp 3 Rramp 1 Vlatch TYPICAL CHARACTERISTICS 14 ...
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... TEMPERATURE (°C) Figure 9. ICC3 vs. Temperature − TEMPERATURE (°C) Figure 11. Drive Sink Resistance vs. Temperature NCP1217, NCP1217A 5.90 5.80 5.70 5.60 5.50 5.40 5.30 100 150 −50 Figure 8. VCC −50 100 150 Figure 10. Drive Source Resistance vs. ...
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... TYPICAL CHARACTERISTICS (continued) 1.20 1.15 1.10 1.05 1.00 − TEMPERATURE (°C) Figure 13. Skip Mode Level vs. Temperature 8.0 7.0 6.0 5.0 4.0 3.0 −50 NCP1217, NCP1217A 3.10 3.05 3.00 2.95 2.90 2.85 2.80 2.75 2.70 100 150 −50 Figure 14. Int Comp Ramp Max Level vs 100 TEMPERATURE (°C) Figure 15. High Voltage Current Source (@ V = 10V) vs. Temperature CC http://onsemi.com 100 TEMPERATURE (°C) ...
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... Wide Switching−Frequency Offer: Three different options are available: 65 kHz – 100 kHz–133 kHz. Depending on the application, the designer can pick up the right device to NCP1217, NCP1217A APPLICATION INFORMATION help reducing magnetics or improve the EMI signature before reaching the 150 kHz starting point. ...
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... DC level interesting to implement a true short−circuit protection. A short−circuit actually forces the output voltage low NCP1217, NCP1217A 12.8 V), the current source turns off and no longer wastes any power. At this time, the V controller and the auxiliary supply is supposed to take over ...
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... IC enters the so−called skip cycle mode, also named controlled burst operation. The power transfer now depends upon the width of the pulse bunches (Figure 20). Suppose we have the following component values: Lp, primary inductance = 350 mH Fsw, switching frequency = 65 kHz Ip skip = 600 mA (or 333 mV/Rsense) NCP1217, NCP1217A VCC = 7.6 V min V CC VCC = 5 ...
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... Sufficient margin shall be kept between normal Pin1 level and the latchoff point in order to avoid false triggering. Ramp Compensation Ramp compensation is a known mean to cure subharmonic oscillations. These oscillations take place at half the switching frequency and occur only during NCP1217, NCP1217A MAX PEAK CURRENT SKIP CYCLE CURRENT LIMIT 882 ...
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... V latch Drv Adj Figure 24. When Vadj is Pulled Above 3.1 V, NCP1217 Permanently Latches−Off the Output Pulses NCP1217, NCP1217A Latching Off the NCP1217 Total latched shutdown can easily be implemented through a simple PNP bipolar transistor as depicted by Figure 23. When OFF transparent to the operation. When forward biased, the transistor pulls the Adj pin toward V and permanently latches− ...
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... This option can easily be accomplished through a single NPN bipolar transistor wired between FB and ground. By pulling FB below the Adj Pin 1 level, the NCP1217, NCP1217A output pulses are disabled as long pulled below Pin 1. As soon relaxed, the IC resumes its operation. ...
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... Cbulk Figure 28. A simple resistor in series avoids any latch−up in the controller . . . NCP1217, NCP1217A Another option (Figure 29) consists in wiring a diode from V CC VCC sooner and thus stops the switching activity before ON the bulk capacitor gets deeply discharged. For security reasons, two diodes can be connected in series ...
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... Soft−Start (NCP1217A only) The NCP1217A features an internal 1.0 ms soft−start activated during the power on sequence (PON). As soon as V reaches VCC , the peak current is gradually CC OFF increased from nearly zero up to the maximum clamping level (e.g. 1.0 V). This situation lasts during 1.0 ms and further to that time period, the peak current limit is blocked to 1.0 V until the supply enters regulation. The soft− ...
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... NCP1217AD133R2G NCP1217AP65 NCP1217AP65G NCP1217AP100 NCP1217AP100G NCP1217AP133 NCP1217AP133G †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specification Brochure, BRD8011/D. NCP1217, NCP1217A Version Marking 65 kHz 17D06 65 kHz 17D06 100 kHz 17D10 100 kHz ...
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... H D 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. NCP1217, NCP1217A PACKAGE DIMENSIONS SOIC−8 NB CASE 751−07 ISSUE 0.10 (0.004) ...
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... Literature Distribution Center for ON Semiconductor P.O. Box 61312, Phoenix, Arizona 85082−1312 USA Phone: 480−829−7710 or 800−344−3860 Toll Free USA/Canada Fax: 480−829−7709 or 800−344−3867 Toll Free USA/Canada Email: orderlit@onsemi.com NCP1217, NCP1217A PACKAGE DIMENSIONS PDIP−7 P SUFFIX CASE 626B−01 ...