LM3687TL-1815EV National Semiconductor, LM3687TL-1815EV Datasheet
LM3687TL-1815EV
Specifications of LM3687TL-1815EV
Related parts for LM3687TL-1815EV
LM3687TL-1815EV Summary of contents
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... The LM3687 is available in a tiny, lead-free (NO PB) 9-bump micro SMD package. A high switching frequency of 1.8MHz (typ.) allows the use of tiny surface-mount components. Only four external components -one inductor and three ceramic capacitors- are required. © 2008 National Semiconductor Corporation Features DC-DC Converter: ■ 750mA maximum load capability ■ ...
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Typical Application Circuit FIGURE 1. Typical Application Circuit: Linear Regulator as Post Regulator FIGURE 2. Typical Application Circuit: Independent Mode of Operation www.national.com 2 20210101 20210105 ...
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Connection Diagrams Connection Diagram 9-Bump Thin Micro SMD Package Top View Large Bump, 0.5mm Pitch, See NS Package TLA09 Note:The actual physical placement of the package marking will vary from part to part. The package marking "X" designates the date ...
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... For availability or other output voltage combinations please contact your local NSC sales office www.national.com + 200mV in order to enable the main regulator (I MAX Order Number Package Marking LM3687TL-1815 S9 S9 LM3687TLX-1815 LM3687TL-1812 SB LM3687TLX-1812 SB LM3687TL-1813 tbd LM3687TLX-1813 tbd 4 = 350mA). MAX = 50mA) is active, supplied from V . BATT Supplied as 250 units, tape and reel, lead free 3000 units, tape and ...
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... Human Body Model: Machine Model ESD Caution Notice National Semiconductor recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper ESD handling techniques can result in damage. Electrical Characteristics 25°C. Limits appearing in boldface type apply over the full operating temperature range: -30°C ...
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Linear Regulator, Normal Mode Symbol Parameter ΔV / Output Voltage OUT_LIN Accuracy V OUT_LIN(NOM) ΔV / OUT_LIN ΔV IN_LIN Line Regulation Error ΔV / OUT_LIN ΔV BATT ΔV / ΔmA Load Regulation Error I OUT_LIN V DO_VIN_LIN Output Voltage Dropout ...
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System Parameters Supply Symbol Parameter I Quiescent current EN_LIN = low, EN_DCDC = high, I Q_VBATT into V I BATT OUT_LIN (FB_DCDC forced higher than V EN_LIN = high, EN_DCDC = low EN_LIN = EN_DCDC = high Shutdown current into ...
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... Note 3: Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages 140°C (typ.). Note 4: For detailed soldering specifications and information, please refer to National Semiconductor Application Note 1112: Micro SMD Wafer Level Chip Scale Package (AN-1112). Note 5: The Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin ...
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Block Diagram Simplified Block Diagram 9 20210106 www.national.com ...
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Typical Performance Characteristics V = 3.6V 25°C, enable pins tied to V BATT LDO disabled Q_VBATT BATT V vs. I OUT_DCDC V vs. Temperature OUT_DCDC www.national.com Unless otherwise specified, typical application (post regulation), ...
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Efficiency DC-DC vs. Output Current LDO disabled 20210134 Startup into load V Line Transient Response IN_LIN Startup into no load V Line Transient Response (PWM Mode) BATT 20210116 Load Transient Response DC-DC (PWM Mode: 100mA to 750mA) 20210118 11 20210115 ...
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Load Transient Response DC-DC (PFM Mode: 1mA to 50mA) Mode Change by Load Transients (PFM to PWM) Output Ripple PFM Mode www.national.com Load Transient Response Linear Regulator 0mA to 350mA 20210120 Mode Change by Load Transients (PWM to PFM) 20210122 ...
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Operation Description DEVICE INFORMATION The LM3687 incorporates a high efficiency synchronous switching step-down DC-DC converter and a very low dropout linear regulator. The DC-DC converter delivers a constant voltage from a sin- gle Li- Ion battery and input voltage rails ...
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If the output is shorted to ground the device enters a timed current limit mode where the NFET is turned on for a longer duration until the inductor current falls below a low threshold. This ...
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Soft Start The DC-DC converter 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_DCDC goes from logic low to logic high after ...
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Application Hints INDUCTOR SELECTION There are two main considerations when choosing an induc- tor; the inductor should not saturate, and the inductor current ripple should be small enough to achieve the desired output voltage ripple. Different saturation current rating specifica- ...
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The ESR (Equivalent Series Resistance) of this input capac- itor should be in the range of 3mΩ to 300mΩ. The tolerance and temperature coefficient must be considered when select- ...
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Another important consideration is that tantalum capacitors have higher ESR values than equivalent size ceramics. This means that while it may be possible to find a tantalum capac- ...
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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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FIGURE 8. Top Layer Board Layout 20 20210133 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 9-Bump Thin Micro SMD Package, Large Bump, 0.5mm Pitch For most accurate revision please refer to www.national.com/packaging/parts/ NS Package Number TLA09BBA The dimensions for X1, X2 and X3 are given as ...
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