LM3671MFX-1.8 National Semiconductor, LM3671MFX-1.8 Datasheet
LM3671MFX-1.8
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LM3671MFX-1.8 Summary of contents
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... Features n 16 µA typical quiescent current n 600 mA maximum load capability Typical Application Circuits © 2004 National Semiconductor Corporation n 2 MHz PWM fixed switching frequency (typ) n Automatic PFM/PWM mode switching n Available in fixed output voltages and adjustable version n SOT23-5 package ...
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Typical Application Circuits FIGURE 2. Typical Application Circuit for ADJ version Connection Diagram and Package Mark Information Note: The actual physical placement of the package marking will vary from part to part. Pin Description Pin # Name ...
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... 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-1.8 1.875 LM3671MF-1.875 LM3671MFX-1.875 LM3671MF-1.875 LM3671MFX-1.875 * ADJ, 1.2 and 1.25V to be released soon.Samples available now. Spec Package Marking NOPB NOPB SBTB NOPB NOPB SBPB NOPB NOPB SDRB NOPB NOPB SEDB ...
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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 FB, SW, EN Pin: Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX Storage Temperature Range Maximum Lead Temperature (Soldering, 10 sec.) ...
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Electrical Characteristics type apply over the full operating junction temperature range (−25˚C ≤ T apply to the LM3671 Typical Application Circuit (Figure. 1) with V Note 8: Refer to datasheet curves for closed loop data and its variation with regards ...
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FIGURE 4. Simplified Functional Diagram 6 20108418 ...
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Typical Performance Characteristics LM3671MF, Circuit of Figure 3.6V Quiescent Supply Current vs. Supply Voltage Output Voltage vs. Supply Voltage (V = 1.5V) OUT Output Voltage vs. Output Current (V = 1.5V) OUT = 25˚C, unless ...
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Typical Performance Characteristics Efficiency vs. Output Current (V = 1.5V, L= 2.2 µH) OUT Switching Frequency vs. Temperature Line Transient Response (PWM Mode) www.national.com (Continued) Efficiency vs. Output Current (V OUT 20108408 Open/Closed Loop Current Limit vs. Temperature 20108410 Load ...
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Typical Performance Characteristics Load Transient Response (PFM Mode 0.5mA to 50mA) Mode Change by Load Transients (PFM to PWM) Start Up into PWM Mode (Output Current= 300mA) (Continued) Load Transient Response (PFM Mode 50mA to 0.5mA) 20108414 Mode Change by ...
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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 either a single Li-Ion or three cell NiMH/NiCd battery to portable devices such as cell phones and PDAs. Using a ...
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Operation Description FIGURE 6. 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 tions when the supply is less than 2.8V. Do not leave the EN pin floating. Do not tie EN pin to V ≥ 2.5V) with a slow input supply ramp. LM3671-ADJ (V OUT SOFT START The LM3671 has ...
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Application Information LM3671-ADJ configurations for various V V (V) R1(kΩ) R2 (kΩ) OUT 0.7 54.9 137 0.8 118 196 0.9 162 200 1.0 200 200 1.1 191 158 1.2 280 200 1.5 360 180 1.6 442 200 1.7 432 180 ...
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Application Information Model DO3314-222MX LPO3310-222MX ELL5GM2R2N CDRH2D14-2R2 OUTPUT CAPACITOR SELECTION Use a 22 µF, 6.3V ceramic capacitor. Use X7R or X5R types, do not use Y5V. DC bias characteristics of ceramic capaci- tors must be considered when selecting case sizes ...
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Application Information FIGURE 8. Board Layout Design Rules for the LM3671 Good layout for the LM3671 can be implemented by follow- ing a few simple design rules, as illustrated in Figure 8. 1. Place the LM3671, inductor and filter capacitors ...
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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’’ as defined in CSP-9-111S2. ...