NCP1212P ON Semiconductor, NCP1212P Datasheet
NCP1212P
Specifications of NCP1212P
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NCP1212P Summary of contents
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... BOK (Top View) ORDERING INFORMATION Device Package NCP1212DR2G SOIC--8 (Pb--Free) NCP1212PG PDIP--8 (Pb--Free) †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. 1 MARKING DIAGRAM 8 N1212 ALYW ...
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Figure 1. Typical Application Circuit http://onsemi.com 2 ...
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Figure 2. Simplified Functional Block Diagram http://onsemi.com 3 CLK CLK ...
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PIN FUNCTION DESCRIPTION Pin Name Function 1 FB Feedback Input 2 BOK Brownout Detect with Hysteresis 3 CS Current Sense Input 4 CT Programmed Oscillator Frequency 5 GND IC Ground 6 DRV Gate Driver Output 7 VCC Positive Supply to ...
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ELECTRICAL CHARACTERISTICS unless otherwise noted.) CC Characteristic OSCILLATOR SECTION Oscillation Frequency C (DMAX = 48 Oscillation Frequency C (DMAX = 82 Frequency Change against ...
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T , JUNCTION TEMPERATURE (C) J Figure 3. Oscillator Frequency with 48% Duty Cycle vs. Junction Temperature 0.12 0.1 0.08 0.06 0.04 0. JUNCTION ...
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T , JUNCTION TEMPERATURE (C) J Figure 9. Soft- -Start Charge Current vs. Junction Temperature -- JUNCTION TEMPERATURE ...
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T , JUNCTION TEMPERATURE (C) J Figure 15. Gate Drive Voltage Rise Time vs. Junction Temperature 1.4 1.3 1.2 1.1 1.0 0.9 0.8 -- JUNCTION ...
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T , JUNCTION TEMPERATURE (C) J Figure 21. V Under Voltage Lockout CC Threshold vs. Junction Temperature -- ...
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Figure 27. Rise Time of Gate Drive Waveform ( nF Ramp 3.5 Ramp down from 2.5 2 1.5 1 0.5 0 --0 SUPPLY ...
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INTRODUCTION The NCP1212 implements a standard current mode architecture where the switch- -off time is dictated by the peak current setpoint. This device represents an ideal candidate where low external part- -count is the key system requirement. Additionally, the device ...
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Current Sense Section The current sense pin, CS detects the voltage drop across a current sensing resistor, R connected in between the sense power MOSFET and Ground. In most cases, a narrow spike on the leading edge of the current ...
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C T Figure 35. Output Pulse Duty Cycle Depends on the SS/DMAX Pin Voltage SS/DMAX pin is also used for the selection of maximum turn on Duty Cycle. The oscillator circuit is designed to operate in either 82% or 48% ...
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Current Limit From Current -- Sense + + Max. Duty OSC DMAX Cycle CT Clock 48% or 82 Brownout Protection NCP1212 has a built- -in comparator for brownout detection as shown in Figure ...
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To Bulk Capacitor R Upper BOK R Lower Internal 5.0 V Regulator A low current 5.0 V regulator is available internally for the device operation and reference voltages generation. This voltage not accessible externally and is designed to operate with ...
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APPLICATION INFORMATION AND TYPICAL WAVEFORMS The NCP1212 is an ideal choice for next generation isolated fix switching frequency forward mode converters that only need few external components to complete the system. Converting your existing application from using UC384X controllers to ...
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the internal current source for typical. The discharging time for 0.22 mF Soft- -Start capacitor is: 0.22 mF × (5.0 V − 0.6 V − 0 DIS = 20 ...
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Channel 1: The MOSFET’s V Channel 2: Primary Bulk Capacitor Voltage Channel 3: BOK Pin Voltage Experimental results for the Brownout action were shown in Figure 42. From the captured waveforms, it can be noted that the Brownout Input Threshold ...
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VCC R8 Q1 2.5 K PNP + 100 3 Q2 PNP 0.1 Figure 43. Suggested Solution for Better Light Load Regulation The skip mode operation waveform at light load ...
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... S B 0.25 (0.010 - 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. PACKAGE DIMENSIONS SOIC SUFFIX CASE 751--07 ISSUE 0.10 (0.004 SOLDERING FOOTPRINT* 1.52 0.060 7.0 4.0 ...
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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 ...