LM22672MR-5.0 NSC [National Semiconductor], LM22672MR-5.0 Datasheet
LM22672MR-5.0
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LM22672MR-5.0 Summary of contents
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SIMPLE SWITCHER®, Step-Down Voltage Regulator with Features General Description The LM22672 series of regulators are monolithic integrated circuits which provide all of the active functions for a step- down (buck) switching regulator capable of driving loads ...
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... Connection Diagram Ordering Information Output Voltage Order Number ADJ LM22672MR-ADJ ADJ LM22672MRE-ADJ ADJ LM22672MRX-ADJ 5.0 LM22672MR-5.0 5.0 LM22672MRE-5.0 5.0 LM22672MRX-5.0 Pin Descriptions Pin Name Description 1 BOOT Bootstrap input 2 SS Soft-start pin 3 RT/SYNC Oscillator frequency adjust pin or frequency synchronization 4 FB Feedback pin 5 EN Precision enable pin ...
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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 ...
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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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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 resistor to ground. The diagram in this ...
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F is the switching frequency which is 500 kHz without an external frequency set resistor or external sync signal ap- plied to the RT/SYNC pin. If the switching frequency is set higher than 500kHz, the inductance value may not ...
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FIGURE 5. Resistive Feedback Divider A maximum value of 10 kΩ is recommended for the sum of R1 and R2 to keep high output voltage accuracy for the –ADJ option. A maximum of 2 kΩ is recommended for the -5.0 ...
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The junction-to-ambient thermal resistance of the LM22672 will vary with the application. The most signifi- cant variables are the area of copper in the PC board, the number of ...
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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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