LM22678TJ-ADJ/NOPB National Semiconductor, LM22678TJ-ADJ/NOPB Datasheet
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LM22678TJ-ADJ/NOPB
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LM22678TJ-ADJ/NOPB Summary of contents
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... The LM22678 series also has built in thermal shutdown, current limiting and an enable control input that can power down the regulator to a low 25 µA quiescent current standby condition. Simplified Application Schematic © 2010 National Semiconductor Corporation LM22678/LM22678Q Features ■ Wide input voltage range: 4.5V to 42V ■ ...
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... Output Order Number Voltage ADJ LM22678TJE-ADJ ADJ LM22678TJ-ADJ 5.0 LM22678TJE-5.0 5.0 LM22678TJ-5.0 ADJ LM22678QTJE-ADJ ADJ LM22678QTJ-ADJ 5.0 LM22678QTJE-5.0 5.0 LM22678QTJ-5.0 *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies. Reliability qualification is compliant with the requirements and temperature grades defined in the AEC-Q100 standard. Automotive grade products are identified with the letter Q ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND EN Pin Voltage SW to GND (Note 2) BOOT Pin Voltage FB Pin Voltage Power Dissipation Electrical Characteristics junction temperature (T ) range of -40°C to +125°C. Minimum and Maximum limits are guaranteed through test, design, or statistical J correlation ...
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Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond ...
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Feedback Bias Current vs Temperature Standby Quiescent Current vs Input Voltage Normalized Feedback Voltage vs Input Voltage Normalized Enable Threshold Voltage vs Temperature 30076105 Normalized Feedback Voltage vs Temperature 30076106 30076109 5 30076110 30076107 www.national.com ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 1. 3. OUT 6 30076114 ...
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Detailed Operating Description The LM22678 switching regulator features all of the functions necessary to implement an efficient high voltage buck regu- lator using a minimum of external components. This easy to use regulator integrates a 42V N-Channel switch with an ...
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FIGURE 2. Output Current in Foldback vs. Nominal Duty Cycle The percentage of output current limit fold back is affected by duty cycle, inductance, and See Figure 2 for details. The current limit will only protect the inductor from a ...
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Application Information EXTERNAL COMPONENTS The following design procedures can be used to design a non- synchronous buck converter with the LM22678. Inductor The inductor value ...
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Where V = 1.285V typical for the -ADJ option and 5V for the FB -5.0 option FIGURE 3. Resistive Feedback Divider A maximum value of 10 kΩ is recommended for the sum of R1 and R2 to keep ...
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Circuit Board Layout Board layout is critical for switching power supplies. First, the ground plane area must be sufficient for thermal dissipation purposes. Second, appropriate guidelines must be followed to reduce the effects of switching noise. Switch mode con- verters ...
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PCB Layout Example www.national.com 30076125 12 ...
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Schematic for Buck/Boost (Inverting) Application See AN-1888 for more information on the inverting (buck- boost) application generating a negative output voltage from a positive input voltage. 13 30076126 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 7-Lead Plastic TO-263 THIN Package NS Package Number TJ7A 14 ...
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Notes 15 www.national.com ...
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