NCP1212_05 ONSEMI [ON Semiconductor], NCP1212_05 Datasheet
NCP1212_05
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NCP1212_05 Summary of contents
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NCP1212 Current Mode PWM Controller for Both Forward and Flyback Converters NCP1212 is a high performance current mode PWM controller specifically designed for off−line and DC−to−DC converter applications. The device requires very few external components and offers designer additional protection ...
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NCP1212 Figure 1. Typical Application Circuit http://onsemi.com 2 ...
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NCP1212 CLK Figure 2. Simplified Functional Block Diagram http://onsemi.com 3 CLK ...
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ELECTRICAL CHARACTERISTICS (For typical values unless otherwise noted.) CC Characteristic OSCILLATOR SECTION ° Oscillation Frequency (DMAX = 48 ° Oscillation Frequency (DMAX = 82%, C ...
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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 0.02 0 − JUNCTION ...
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T , JUNCTION TEMPERATURE (°C) J Figure 9. Soft−Start Charge Current vs. Junction Temperature − JUNCTION TEMPERATURE (°C) ...
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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 provides extensive ...
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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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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% charging time that corresponds to either 82% or 48% maximum PWM turn on Duty ...
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Current Limit From − Current + Sense + 1 V − Max. Duty OSC DMAX Cycle CT Clock 48% or 82% + 3.2 V − Brownout Protection NCP1212 has a built−in comparator for brownout detection as shown in Figure 39. ...
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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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I −I is the internal current source for typical. The discharging time for 0.22 mF Soft−Start capacitor is: 0. DIS + 20 mA Figure 41. ...
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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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0.25 (0.010 −Y− SEATING PLANE −Z− 0.25 (0.010 *For additional information on our Pb−Free strategy and soldering details, please download the ON ...
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F −A− NOTE 2 C −T− N SEATING PLANE 0.13 (0.005) M NCP1212 PACKAGE DIMENSIONS PDIP−8 N SUFFIX CASE 626−05 ISSUE http://onsemi.com ...
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The product described herein (NCP1212), may be covered by one or more of the following U.S. patents: 6,385,060, 6,385,061, and 6,271,735. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC ...