ncp1442 ON Semiconductor, ncp1442 Datasheet
ncp1442
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ncp1442 Summary of contents
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... NCP1444, NCP1445 4.0 A 280 kHz/560 kHz Boost Regulators The NCP1442/3/4/5 products are 280 kHz/560 kHz switching regulators with a high efficiency, 4.0 A integrated switch. These parts operate over a wide input voltage range, from 2 The flexibility of the design allows the chips to operate in most power supply configurations, including boost, flyback, forward, inverting, and SEPIC ...
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... MBRS320T3 GND SS Figure 1. Application Diagram − NCP1442/4, 3 5.0 V/1.5 A Boost Converter Rating On Cold Plate (25° MAX MIN −0 −0 6.0 V −0 −0.3 V NFB 10 V −10 V Test 6 ...
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... NFB = −3 sinks Reduce V from 1.5 V until switching stops C NCP1442/ 1 NFB = −1.9 V NCP1442/ NFB = 0 V NCP1442/3 NCP1444/ 1 NFB = −1.9 V NCP1444/ NFB = 0 V NCP1444/5 Frequency drops to reduced operating frequency Frequency drops to reduced operating frequency ...
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... ELECTRICAL CHARACTERISTICS NCP1442/3/4/5 specifications unless otherwise stated.) (See Note 2) Characteristic Power Switch Switch Saturation Voltage Switch Current Limit Minimum Pulse Width Switch Transconductance DIV CC SW Switch Leakage General Operating Current Shutdown Mode Current Minimum Operation Input Voltage Thermal Shutdown Thermal Hysteresis 4 ...
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... V CC Shutdown 2.0 V Regulator Delay Timer Sync SS 200 k Negative 2.0 V Error Amp 250 k NFB + NCP1443/5 − only −0.65 V Detector 0.4 V Detector FB − NCP1442/4 + only 1.276 V Thermal Shutdown S PWM Oscillator Latch R Frequency Shift 5:1 + Positive Error Amp V C Figure 2. Block Diagram http://onsemi.com 5 Switch Q Driver ×5 ...
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... Figure 8. Switching Frequency versus Positive http://onsemi.com 2 2. AMBIENT TEMPERATURE (° versus Temperature AMBIENT TEMPERATURE (°C) A Temperature (NCP1442/3 Only 25° 85° 0.40 0.41 0.42 0.43 0.44 , POSITIVE FEEDBACK VOLTAGE (V) Feedback Voltage 80 80 0.45 ...
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... Figure 14. Maximum Duty Cycle versus http://onsemi.com AMBIENT TEMPERATURE (°C) A Temperature (NCP1442/4 Only AMBIENT TEMPERATURE (°C) A Temperature (NCP1442/3 Only 2 AMBIENT TEMPERATURE (°C) A Temperature ...
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... Figure 15. V Threshold Voltage versus C Temperature 180 160 140 120 100 AMBIENT TEMPERATURE (°C) A Figure 17. Shutdown Delay versus Temperature (NCP1442) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 (V) SS Figure 19. I versus V SS 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0 ...
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T , AMBIENT TEMPERATURE (°C) A Figure 21. Error Amplifier Transconductance versus Temperature 100 0 −100 −200 −300 −400 −500 −0.25 −0.2 −0.15 −0.1 −0.05 0 ...
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... Figure 27. Timing Diagram of Sync and Shutdown APPLICATIONS INFORMATION The oscillator is trimmed to guarantee frequency accuracy. The output of the oscillator turns on the power switch at a frequency of 280 kHz (NCP1442/3) or 560 kHz (NCP1444/5), as shown in Figure 26. The power switch is turned off by the output of the PWM Comparator TTL− ...
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... Bode plot shown in Figure 31. V OUT NCP1442/3/4/5 Figure 30. A Typical Compensation Network The high DC gain in Figure 31 is desirable for achieving DC accuracy over line and load variations. The DC gain of a transconductance error amplifier can be calculated as follows: where error amplifier transconductance ...
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The low frequency pole determined by the error P1, amplifier output resistance and C1 as 2pC1R O The first zero generated by C1 and R1 is 2pC1R1 The phase lead ...
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... OUT * RIPPLE + (f)(L)(V OUT) where 280 kHz for NCP1442/3 and 560 kHz for NCP1444/5. The peak inductor current is equal to average current plus half of the ripple current, which should not cause inductor saturation. The above equation can also be referenced when selecting the value of the inductor based on the tolerance of the ripple current in the circuits ...
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I . Summing up, the output voltage peak−peak IN ripple can be calculated by OUT OUT(RIPPLE OUT) (f) I OUT OUT )(f) The ...
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... Soft−Start Through the addition of an external circuit, a soft−start function can be added to the NCP1442/3/4/5 family of components. Soft−start circuitry prevents the V slamming high during startup, thereby inhibiting the R3 inductor current from rising at a high slope. ...
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... Calculating Junction Temperature To ensure safe operation of the NCP1442/3/4/5, the designer must calculate the on−chip power dissipation and determine its expected junction temperature. Internal thermal protection circuitry will turn the part off once the junction temperature exceeds 180°C ± 30°. However, repeated operation at such high temperatures will ensure a reduced operating life ...
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... junction−to−ambient thermal resistance (°C/W). JA For ON Semiconductor components, the value for q be found on page 19 of the datasheet, under “Package Thermal Data.” Note that this value is different for every package style and every manufacturer. For the NCP144X, q varies between 10− ...
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... ORDERING INFORMATION Operating Temperature Range Device NCP1442FR4 NCP1442FR4G NCP1442T NCP1443FR4 NCP1443FR4G 0°C < T NCP1443T NCP1444FR4 NCP1444T NCP1445FR4 NCP1445T †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. Package 7 Lead PowerFLEX Short− ...
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0.076 (0.003) S −T− K SEATING PLANE THERMAL DIE PAD PACKAGE THERMAL DATA R qJC R qJA *Depending on thermal properties of substrate. R PACKAGE ...
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... K 24.00 26.54 0.945 1.045 L 26.67 29.03 1.050 1.143 M 6.10 6.48 0.240 0.255 N 7 −−− 7 −−− ° ° Q 3.53 3.96 0.139 0.156 ° ° ° ° ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1442/D ...