NCP1215A ON Semiconductor, NCP1215A Datasheet
NCP1215A
Related parts for NCP1215A
NCP1215A Summary of contents
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... Low Cost Variable OFF Time Switched Mode Power Supply Controller The NCP1215A is a controller for low power off−line flyback Switched Mode Power Supplies (SMPS) featuring low size, weight and cost constraints together with a good low standby power performance. The operating principle uses switching frequency reduction at light load by increasing the OFF Time ...
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... If your application requires a gate−source resistor, please refer to design guidelines in this document. Feedback Loop FB Control − V offset + 0− 12.5−50 mA Current Sense Comparator + − GND Figure 2. Representative Block Diagram NCP1215A + GND Gate Figure 1. Typical Application V DD Reference I Regulator ...
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... Tape and Reel Packaging Specifications Brochure, BRD8011/D. NCP1215A Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á ...
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... Undervoltage Lockout Threshold Voltage Hysteresis (V − startup UVLO V Startup Current Consumption ( Steady State Current Consumption 1.0 nF 100 kHz, FB open) GATE SW NCP1215A ( for typical values T = 25°C, for min/max values Symbol offset CT−25mA ) V offset CT−50mA V CT−max V CT− ...
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... T , JUNCTION TEMPERATURE (°C) J Figure 5. Operating Current Consumption vs. Junction Temperature 49.0 48.5 48.0 47.5 47.0 46.5 46.0 45.5 − JUNCTION TEMPERATURE (°C) J Figure 7. Current Sense Source Current vs. Junction Temperature NCP1215A TYPICAL CHARACTERISTICS 8.8 8.7 8.6 8.5 8.4 8.3 8.2 75 100 125 −25 0 Figure 4. V 1.20 1.18 1.16 1.14 1.12 1.10 1.08 1.06 1.04 1.02 1.00 75 100 125 −25 0 Figure 6 ...
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... Figure 9. CT Pin Source Current vs. Junction Temperature 120 100 R source sink − JUNCTION TEMPERATURE (°C) J Figure 11. Drive Sink and Source Resistance vs. Junction Temperature NCP1215A 100 125 −25 0 Figure 10. CT Pin Threshold vs. Junction 60.0 50.0 40.0 30.0 20.0 10.0 0.0 75 100 125 0 Figure 12 ...
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... The NCP1215A implements a current mode SMPS with a variable OFF time dependant upon output power demand. It can be seen from the typical application that NCP1215A is designed to operate with a minimum number of external component. The NCP1215A incorporates the following features: • Frequency Foldback: Since the switch−off time increases when power demand decreases, the switching frequency naturally diminishes in light load conditions ...
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... OFF Time Control The loop signal together with the internal current source, via an external capacitor, controls the switch−off time. This is portrayed in Figure 17. NCP1215A CS 12 During the switch− ...
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... Turn−on Figure 20. CS Pin Voltage Figure 20 also shows the effect of the inductor current of differing output power demand. NCP1215A The primary current sensing method we described, brings the following benefits compared to the traditional approach: • Maximum peak voltage across the current sense resistor is determined and can be optimized by the value of the shift resistor ...
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... The range of the frequency change is sufficient to keep output voltage regulation in any light load condition. NCP1215A Application Design Example An example of the typical wall adapter application is described hereafter wall adapter it should be able to operate properly with (eq ...
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... 2.442 ppk 0.2047 NCP1215A The voltage drop across the sense resistor needs to be recalculated: flux density · I ppk + 2.7 · 0.2047 + 0.553 V Using the above results the value of the shift resistor is: R shift + (eq. 20) ...
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... R1 GND 2.7 NCP1215A The following oscilloscope snapshots illustrate the operation of the working adapter. The Channel 3 in Figure 22 shows CT pin voltage at full output load. The Channel gate driver output. Figure 22. CT Voltage at Full Load Condition NCP1215A + R3 C5 2M7 D5 100 LL4448 ...
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... However, dealing with an extremely low startup current implies a careful selection of the gate−source resistance. With the NCP1215A, the gate−source resistor must be calculated to allow the growth of the order to not interfere with the power−on sequence ...
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... PLANE −Z− 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. NCP1215A PACKAGE DIMENSIONS SOIC−8 D SUFFIX CASE 751−07 ISSUE ...
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... Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. NCP1215A PACKAGE DIMENSIONS TSOP−6 CASE 318G−02 ISSUE P NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. ...
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... The product described herein (NCP1215A), may be covered by the following U.S. patents: 6,385,060, 6,605,978. 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 further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “ ...