LM22672MR-ADJ/NOPB National Semiconductor, LM22672MR-ADJ/NOPB Datasheet
LM22672MR-ADJ/NOPB
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LM22672MR-ADJ/NOPB Summary of contents
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... An adjustable soft-start feature is provided by selecting an appropriate external soft-start capacitor. Simplified Application Schematic © 2011 National Semiconductor Corporation LM22672/LM22672Q Features ■ Wide input voltage range: 4.5V to 42V ■ ...
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... Order Number Voltage ADJ LM22672MR-ADJ ADJ LM22672MRE-ADJ ADJ LM22672MRX-ADJ 5.0 LM22672MR-5.0 5.0 LM22672MRE-5.0 5.0 LM22672MRX-5.0 ADJ LM22672MR-ADJ ADJ LM22672QMRE-ADJ ADJ LM22672QMRX-ADJ 5.0 LM22672QMR-5.0 5.0 LM22672QMRE-5.0 5.0 LM22672QMRX-5.0 *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies. ...
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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 SS, RT/SYNC Pin Voltage SW to GND (Note 2) BOOT Pin Voltage FB Pin Voltage Power Dissipation Electrical Characteristics junction temperature (T ) range of -40° ...
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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 30076705 Normalized Feedback Voltage vs Temperature 30076706 Switching Frequency vs RT/SYNC Resistor 30076709 5 30076710 30076707 30076713 ...
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Soft-start Current vs Temperature www.national.com 30076742 6 ...
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Typical Application Circuit and Block Diagram FIGURE 1. 3. 600 kHz OUT 7 30076714 www.national.com ...
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Detailed Operating Description The LM22672 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 switching See Figure 2 for details. The current limit will only protect the inductor from ...
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FIGURE 3. Switching Frequency vs RT/SYNC Resistor Self Synchronize It is also possible to self-synchronize multiple LM22672 reg- ulators to share the same switching frequency. This can be done by attaching the RT/SYNC pins together and putting a 1 kΩ ...
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Application Information EXTERNAL COMPONENTS The following design procedures can be used to design a non- synchronous buck converter with the LM22672. Inductor The inductor value is determined based on the load current, ripple current, and the minimum and maximum input ...
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The resistor values can be determined by the following equa- tions: -ADJ option: -5.0 option: Where V = 1.285V typical for the -ADJ option and 5V for the FB -5.0 option FIGURE 5. Resistive Feedback Divider A maximum value of ...
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LM22672 is to measure the total conversion losses (Pin – Pout) then subtract the power losses in the Schottky diode and output inductor. An approximation for the Schottky diode loss is ...
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PCB Layout Example www.national.com 14 30076741 ...
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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. 30076726 15 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 8-Lead Plastic PSOP-8 Package NS Package Number MRA08B 16 ...
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Notes 17 www.national.com ...
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