LM3670MFX-2.5 National Semiconductor, LM3670MFX-2.5 Datasheet
LM3670MFX-2.5
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LM3670MFX-2.5 Summary of contents
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... MHz (typ) - allows use of tiny surface-mount components. Only three external surface- mount components, an inductor and two ceramic capacitors, are required. Typical Application FIGURE 1. 1.8V - Fixed Output Voltage - Typical Application Circuit © 2004 National Semiconductor Corporation Features adj (.7V min), 1.2, 1.5, 1.6, 1.8, 1.875, 2.5, 3.3V OUT n 2.5V ≤ V ≤ ...
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Typical Application (Continued) FIGURE 2. 1.2V - Adjustable Output Voltage - Typical Application Circuit Connection Diagram and Package Mark Information Note: The actual physical placement of the package marking will vary from part to part. Pin Descriptions Pin # Name ...
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... Ordering Information Voltage Option Order Number (V) (Level 95) 3.3 LM3670MF-3.3 LM3670MFX-3.3 LM3670MF-3.3 LM3670MFX-3.3 2.5 LM3670MF-2.5 LM3670MFX-2.5 LM3670MF-2.5 LM3670MFX-2.5 1.875 LM3670MF-1.875 LM3670MFX-1.875 LM3670MF-1.875 LM3670MFX-1.875 1.8 * LM3670MF-1.8 LM3670MFX-1.8 LM3670MF-1.8 LM3670MFX-1.8 1.6 LM3670MF-1.6 LM3670MFX-1.6 LM3670MF-1.6 LM3670MFX-1.6 1.5 LM3670MF-1.5 LM3670MFX-1.5 LM3670MF-1.5 LM3670MFX-1.5 1.2 LM3670MF-1.2 LM3670MFX-1.2 LM3670MF-1.2 LM3670MFX-1.2 Adjustable * ...
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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. V Pin: Voltage to GND IN EN Pin: Voltage to GND FB, SW Pin: Junction Temperature (T ) J-MAX Storage Temperature Range Maximum Lead Temperature (Soldering, 10 sec.) Electrical Characteristics the full operating junction temperature range (− ...
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Electrical Characteristics the full operating junction temperature range (−40˚C ≤ =150mA, EN=V (Continued Symbol Parameter V Logic High Input IH V Logic Low Input IL I Enable (EN) Input Current EN F Internal Oscillator Frequency OSC ...
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FIGURE 4. Simplified Functional Diagram 6 20075832 ...
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Typical Performance Characteristics I vs (output pulled above regulation voltage) V vs. V OUT IN Efficiency vs. I OUT (unless otherwise stated 20075804 20075806 20075808 7 =3.6V, V =1.8V) IN OUT Shutdown vs. Temp ...
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Typical Performance Characteristics Frequency vs. Temperature Line Transient vs. Time IN OUT V = 2.6V to 3.6V IN Line Transient vs. Time IN OUT V = 3. 100 mA) ...
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Typical Performance Characteristics Load Transient vs. Time OUT LOAD I = 3mA to 280mA LOAD Load Transient vs. Time OUT LOAD I = 0mA to 280mA LOAD Load Transient vs. Time ...
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Typical Performance Characteristics PFM Mode OUT INDUCTOR Soft Start OUT INDUCTOR (I = 350mA) LOAD Operation Description DEVICE INFORMATION The LM3670, a high efficiency step down DC-DC switching ...
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Operation Description off, blocking current flow from the input, and then turns the NFET synchronous rectifier on. The inductor draws current from ground through the NFET to the output filter capacitor and load, which ramps the inductor current down with ...
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Operation Description FIGURE 5. Operation in PFM Mode and Transfer to PWM Mode Soft-Start The LM3670 will have a soft-start circuit that limits in-rush current during start-up. Typical currents and times are: Current (mA) Duration (µSec 140 280 ...
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Application Information OUTPUT VOLTAGE SELECTION FOR ADJUSTABLE LM3670 The output voltage of the adjustable parts can be pro- grammed through the resistor network connected from the to GND. V will be adjusted to make V FB OUT ...
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Application Information Model IDC2512NB100M DO1608C-103 ELL6RH100M CDRH5D18-100 OUTPUT CAPACITOR SELECTION The output filter capacitor smoothes out current flow from the inductor to the load, helps maintain a steady output voltage during transient load changes and reduces output voltage ripple. These ...
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Application Information BOARD LAYOUT CONSIDERATIONS PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance of a FIGURE 6. Board Layout Design Rules for the LM3670 Good layout for the LM3670 can ...
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Application Information In mobile phones, for example, a common practice is to place the DC-DC converter on one corner of the board, arrange the CMOS digital circuitry around it (since this also www.national.com generates noise), and then place sensitive preamplifiers ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’ ...