LM22671MRX-5.0/NOPB National Semiconductor, LM22671MRX-5.0/NOPB Datasheet
LM22671MRX-5.0/NOPB
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LM22671MRX-5.0/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 LM22671/LM22671Q Features ■ Wide input voltage range: 4.5V to 42V ■ ...
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... Output Voltage Order Number ADJ LM22671MR-ADJ ADJ LM22671MRE-ADJ ADJ LM22671MRX-ADJ 5.0 LM22671MR-5.0 5.0 LM22671MRE-5.0 5.0 LM22671MRX-5.0 ADJ LM22671QMR-ADJ ADJ LM22671QMRE-ADJ ADJ LM22671QMRX-ADJ 5.0 LM22671QMR-5.0 5.0 LM22671QMRE-5.0 5.0 LM22671QMRX-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 30076805 Normalized Feedback Voltage vs Temperature 30076806 Switching Frequency vs RT/SYNC Resistor 30076809 5 30076810 30076807 30076813 ...
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Soft-start Current vs Temperature www.national.com 30076842 6 ...
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Typical Application Circuit and Block Diagram FIGURE 1. 3. 500 mA at 600 kHz OUT 7 30076814 www.national.com ...
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Detailed Operating Description The LM22671 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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Current Limit When the power switch turns on, the slight capacitance load- ing of the Schottky diode, D1, causes a leading-edge current spike with an extended ringing period. This spike can cause the current limit comparator to trip prematurely. A ...
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FIGURE 3. Switching Frequency vs RT/SYNC Resistor Self Synchronize It is also possible to self-synchronize multiple LM22671 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 LM22671. Inductor The inductor value is determined based on the load current, ripple current, and the minimum and maximum input ...
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FB pin. Other output voltages can use the -ADJ option with a resistor divider. The resistor values can be determined by the following equa- tions: -ADJ option: -5.0 option: Where V = 1.285V typical for the -ADJ ...
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Thermal Considerations The two highest power dissipating components are the re- circulating diode and the LM22671 regulator IC. The easiest method to determine the power dissipation within the LM22671 is to measure the total conversion losses (Pin – Pout) then ...
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PCB Layout Example www.national.com 14 30076841 ...
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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. 30076826 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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