LM3687TL-1813 NSC [National Semiconductor], LM3687TL-1813 Datasheet
LM3687TL-1813
Related parts for LM3687TL-1813
LM3687TL-1813 Summary of contents
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LM3687 Step-Down DC-DC Converter with Integrated Low Dropout Regulator and Startup Mode General Description The LM3687 is a step-down DC-DC converter with an inte- grated low dropout Linear Regulator optimized for powering ultra-low voltage circuits from a single Li-Ion cell ...
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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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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications pins: Voltage to GND, IN_LIN BATT ≤ IN_LIN BATT V pin to V pin ...
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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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External Components, Recommended Specification Symbol Parameter Output Capacitance for C VOUT_LIN linear regulator Input Capacitance for C VIN_LIN linear regulator Input Capacitance for C VBATT DC-DC converter DC-DC converter output C VOUT_DCDC filter capacitor C ESR of all capacitors ESR ...
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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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If the DC-DC con- verter operates in PWM mode, the PMOS is turned off in case of a thermal shutdown. The Thermal-Overload Protection is designed to protect the LM3687 in the event ...
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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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