LM22673MRE-5.0/NOPB National Semiconductor, LM22673MRE-5.0/NOPB Datasheet
LM22673MRE-5.0/NOPB
Specifications of LM22673MRE-5.0/NOPB
Related parts for LM22673MRE-5.0/NOPB
LM22673MRE-5.0/NOPB Summary of contents
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... The current limit threshold can be adjusted using an external resistor. An ad- justable soft-start feature is provided by selecting an appro- priate external soft-start capacitor. Simplified Application Schematic © 2010 National Semiconductor Corporation LM22673 Features ■ Wide input voltage range: 4.5V to 42V ■ ...
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... Order Number ADJ LM22673MR-ADJ ADJ LM22673MRE-ADJ ADJ LM22673MRX-ADJ ADJ LM22673TJE-ADJ ADJ LM22673TJ-ADJ 5.0 LM22673MR-5.0 5.0 LM22673MRE-5.0 5.0 LM22673MRX-5.0 5.0 LM22673TJE-5.0 5.0 LM22673TJ-5.0 www.national.com 30076240 8-Lead Plastic PSOP-8 Package NS Package Number MRA08B 7-Lead Plastic TO-263 THIN Package NS Package Number TJ7A Package Type ...
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Pin Descriptions Pin Numbers Pin Numbers PSOP-8 TO-263 THIN Name Package Package 1 3 BOOT IADJ GND 7 2 VIN Description Application Information Bootstrap ...
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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 SS, IADJ 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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Normalized Feedback Voltage vs Temperature Normalized Feedback Voltage vs Input Voltage Current Limit vs IADJ Resistor www.national.com Normalized R 30076207 Soft-start Current vs Temperature 30076209 30076213 6 vs Temperature DS(ON) 30076208 30076211 ...
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Typical Application Circuit and Block Diagram FIGURE 1. 3. OUT 7 30076214 www.national.com ...
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Detailed Operating Description The LM22673 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 3. 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 3 for details. The current limit will only protect the inductor from ...
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The peak ramp level of the oscillator signal feeding into the PWM comparator is V /10 which equals a gain of 20dB of IN this modulator stage of the IC. The -5.0 fixed output voltage option has twice the gain ...
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This may offer improved loop bandwidth in some applications. See the Internal Compensation section for more details. For the -ADJ option no resistor divider is required for 1.285V output voltage. The output voltage should be directly con- nected to the ...
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FIGURE 5. Current Flow in a Buck Application Thermal Considerations The two highest power dissipating components are the re- circulating diode and the LM22673 regulator IC. The easiest method to determine the power dissipation within the www.national.com LM22673 is to ...
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PCB Layout Example for TO-263 THIN Package 13 30076225 www.national.com ...
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PCB Layout Example for PSOP-8 Package www.national.com 14 30076241 ...
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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. 15 30076226 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 8-Lead PSOP Package NS Package Number MRA08B 16 ...
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Notes 17 www.national.com ...
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