LM3671MF-1.25 National Semiconductor, LM3671MF-1.25 Datasheet

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... Only three external surface-mount components, an inductor and two ceramic capacitors, are required. Typical Application Circuits © 2005 National Semiconductor Corporation Features n 16 µA typical quiescent current n 600 mA maximum load capability n 2 MHz PWM fixed switching frequency (typ) ...

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Typical Application Circuits FIGURE 2. Typical Application Circuit for ADJ version Connection Diagram and Package Mark Information FIGURE 4. 5-bump Micro SMD Package NS Package Number TLA05CBA www.national.com (Continued) 20108402 FIGURE 3. TopView SOT23-5 Package NS Package Number MF05A 2 ...

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Pin Descriptions (SOT23-5) Pin # Name GND Pin Descriptions (5-bump Micro SMD) Pin # Name GND Description Power supply input. ...

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... Ordering Information (SOT23-5) Voltage Option Order Number ADJ LM3671MF-ADJ LM3671MFX-ADJ LM3671MF-ADJ LM3671MFX-ADJ 1.2 LM3671MF-1.2 LM3671MFX-1.2 LM3671MF-1.2 LM3671MFX-1.2 1.25 LM3671MF-1.25 LM3671MFX-1.25 LM3671MF-1.25 LM3671MFX-1.25 1.375 LM3671MF-1.375 LM3671MFX-1.375 LM3671MF-1.375 LM3671MFX-1.375 1.5 LM3671MF-1.5 LM3671MFX-1.5 LM3671MF-1.5 LM3671MFX-1.5 1.6 LM3671MF-1.6 LM3671MFX-1.6 LM3671MF-1.6 LM3671MFX-1.6 1.8 LM3671MF-1.8 LM3671MFX-1.8 LM3671MF-1.8 LM3671MFX-1 ...

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Ordering Information (5-bump Micro SMD) Voltage Option Order Number ADJ* LM3671TL-ADJ LM3671TLX-ADJ LM3671TL-ADJ LM3671TLX-ADJ 1.2 LM3671TL-1.2 LM3671TLX-1.2 LM3671TL-1.2 LM3671TLX-1.2 1.5 LM3671TL-1.5 LM3671TLX-1.5 LM3671TL-1.5 LM3671TLX-1.5 1.8 LM3671TL-1.8 LM3671TLX-1.8 LM3671TL-1.8 LM3671TLX-1.8 1.875 LM3671TL-1.875 LM3671TLX-1.875 LM3671TL-1.875 LM3671TLX-1.875 2.5* LM3671TL-2.5 LM3671TLX-2.5 LM3671TL-2.5 LM3671TLX-2.5 2.8* ...

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... ESD Rating (Note 4) Human Body Model: V ,GND,SW,FB IN Human Body Model: EN Machine Model: All Pins Electrical Characteristics type apply over the full operating ambient temperature range (−30˚C ≤ T apply to the LM3671MF/TL with V IN Symbol Parameter V Input Voltage Range IN V Feedback Voltage (Fixed) MF ...

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... Electrical Characteristics type apply over the full operating ambient temperature range (−30˚C ≤ T apply to the LM3671MF/TL with 3.6V (Continued) IN Note 6: Junction to ambient thermal resistance is highly application and board layout dependent. In applications where high power dissipation exists, special care must be given to thermal dissipation issues in board design. Specified value of 130 ˚C/W for SOT23-5 is based layer, 4" x 3", 2/1/1/2 oz. Cu board as per JEDEC standards is used ...

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Block Diagram www.national.com FIGURE 5. Simplified Functional Diagram 8 20108418 ...

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... Typical Performance Characteristics LM3671MF/TL, Circuit of Figure Quiescent Supply Current vs. Supply Voltage Feedback Bias Current vs. Temp Output Voltage vs. Temperature (V = 1.5V) OUT = 3.6V 25˚C, unless otherwise noted. A 20108404 20108440 20108406 9 Shutdown Current vs. Temp 20108405 Output Voltage vs. Supply Voltage (V = 1.5V) OUT 20108429 Output Voltage vs. Output Current ( ...

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Typical Performance Characteristics R vs. Temperature DS(ON) Efficiency vs. Output Current (V = 1.5V, L= 2.2 µH, dcr = 200mΩ) OUT Efficiency vs. Output Current (ADJ 2.5V, L= 2.2 µH, dcr = 200mΩ) OUT www.national.com (Continued) Efficiency vs. ...

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Typical Performance Characteristics Switching Frequency vs. Temperature Line Transient Response (PWM Mode) Load Transient Response (PFM Mode 0.5mA to 50mA) (Continued) Open/Closed Loop Current Limit vs. Temperature 20108447 Load Transient Response 20108412 Load Transient Response (PFM Mode 50mA to 0.5mA) ...

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Typical Performance Characteristics Mode Change by Load Transients (PFM to PWM) Start Up into PWM Mode (Output Current= 300mA) www.national.com (Continued) Mode Change by Load Transients (PWM to PFM) 20108420 Start Up into PFM Mode (Output Current= 1mA) 20108424 12 ...

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Operation Description DEVICE INFORMATION The LM3671, a high efficiency step down DC-DC switching buck converter, delivers a constant voltage from a single Li-Ion battery and input voltage rails from 2.7V to 5.5V to portable devices such as cell phones and ...

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Operation Description FIGURE 7. Typical PFM Operation During PFM operation, the converter positions the output voltage slightly higher than the nominal output voltage during PWM operation, allowing additional headroom for voltage drop during a load transient from light to heavy ...

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Operation Description SOFT START The LM3671 has a soft-start circuit that limits in-rush current during start-up. During start-up the switch current limit is increased in steps. Soft start is activated only if EN goes from logic low to logic high ...

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Application Information LM3671-ADJ configurations for various V V (V) R1(kΩ) R2 (kΩ) OUT 1.0 200 1.1 191 1.2 280 1.5 357 1.6 442 1.7 432 1.8 464 1.875 523 2.5 402 2.8 464 3.3 562 INDUCTOR SELECTION There are two ...

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... Micro SMD PACKAGE ASSEMBLY AND USE Use of the Micro SMD package requires specialized board layout, precision mounting and careful re-flow techniques, as detailed in National Semiconductor Application Note 1112. Refer to the section "Surface Mount Technology (SMD) As- sembly Considerations". For best results in assembly, align- ment ordinals on the PC board should be used to facilitate placement of the device ...

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Application Information the circuit board. The trace to each pad should enter the pad with a 90˚ entry angle to prevent debris from being caught in deep corners. Initially, the trace to each pad should be 7 mil wide, for ...

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Application Information FIGURE 9. Top layer board layout for SOT23-5 (Continued) 19 20108449 www.national.com ...

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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 5-Lead SOT23-5 Package NS Package Number MF05A 20 ...

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... BANNED SUBSTANCE COMPLIANCE National Semiconductor manufactures products and uses packing materials that 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’’ as defined in CSP-9-111S2. ...