LM3670MF-ADJ/NOPB National Semiconductor, LM3670MF-ADJ/NOPB Datasheet
LM3670MF-ADJ/NOPB
Specifications of LM3670MF-ADJ/NOPB
LM3670MF-ADJTR
Related parts for LM3670MF-ADJ/NOPB
LM3670MF-ADJ/NOPB Summary of contents
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... Only three external surface- mount components, an inductor and two ceramic capacitors, are required. Typical Application FIGURE 1. Fixed Output Voltage - Typical Application Circuit © 2006 National Semiconductor Corporation Features Adj (0.7V min), 1.2, 1.5, 1.6, 1.8, 1.875, 2.5, OUT 3.3V n 2.5V ≤ ...
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Typical Application (Continued) FIGURE 2. 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 1 V ...
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... 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 LM3670MF-ADJ LM3670MFX-ADJ LM3670MF-ADJ LM3670MFX-ADJ SPEC Package Marking NOPB SDEB NOPB NOPB SDDB ...
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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 ≤ T 150mA (Continued) IN Symbol Parameter I DC Bias Current into Minimum V below which V UVLO IN will be disabled R Pin-Pin ...
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FIGURE 4. Simplified Functional Diagram 6 20075832 ...
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Typical Performance Characteristics I (Non-switching) vs vs. V OUT IN Efficiency vs. I OUT (unless otherwise stated 20075804 20075806 20075808 7 = 3.6V 1.8V) IN OUT I vs. Temp Q 20075805 V vs. ...
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Typical Performance Characteristics Frequency vs. Temperature Line Transient (V = 2.6V to 3.6V LOAD Load Transient I = 3mA to 280mA LOAD www.national.com (unless otherwise stated: V 20075810 = 100 mA) (V 20075812 20075816 8 = 3.6V, V ...
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Typical Performance Characteristics Load Transient I = 0mA to 280mA LOAD Load Transient I = 50mA to 350mA LOAD PFM Mode vs. Time SW OUT INDUCTOR (unless otherwise stated LOAD 20075818 I LOAD ...
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Typical Performance Characteristics Soft Start OUT INDUCTOR (I = 350mA) LOAD Operation Description DEVICE INFORMATION The LM3670, a high efficiency step down DC-DC switching buck converter, delivers a constant voltage from either a single ...
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Operation Description The part automatically transition into PFM mode when either of two conditions occurs for a duration more clock cycles: A. The inductor current becomes discontinuous B. The peak PMOS switch current drops below the I ...
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Operation Description LDO - Low Drop Out Operation The LM3670 can operate at 100% duty cycle (no switching, PMOS switch is completely on) for low drop out support of the output voltage. In this way the output voltage is con- ...
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Application Information noise filtering of the input voltage spikes due to this rapidly changing current. Select an input filter capacitor with a surge current rating sufficient for the power-up surge from the input power source. The power-up surge current is ...
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Application Information TABLE 3. Adjustable LM3670 Configurations for Various V VOUT (V) R1 (KΩ) R2 (KΩ) 1.1 240 1.2 280 1.24 300 1.24 221 1.5 402 1.6 442 1.7 487 1.875 549 2.5 806 www.national.com (Continued) C1 (pF) C2 (pF) ...
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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 arrange the CMOS digital circuitry around it (since this also generates noise), and then place sensitive preamplifiers and www.national.com IF stages on the diagonally opposing corner. Often, the (Continued) sensitive circuitry is shielded with a metal pan and ...
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