LM3691TL-0.9 NSC [National Semiconductor], LM3691TL-0.9 Datasheet

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LM3691 High Accuracy, Miniature 1A, Step-Down DC-DC Converter for Portable Applications General Description The LM3691 step-down DC-DC converter is optimized for powering ultra-low voltage circuits from a single Li-Ion cell or 3 cell NiMH/NiCd batteries. It provides ...

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Connection Diagram and Package Mark Information FIGURE 2. 6-Bump Thin Micro SMD Package, Large Bump Note: The actual physical placement of the package marking will vary from part to part. The package marking “X” designates the date code; “V” is ...

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... Ordering Information Order Number 6–bump Micro Voltage Option V SMD 0.75 LM3691TL-0.75 LM3691TLX–0.75 0.85* LM3691TL-0.85 LM3691TLX–0.85 0.9* LM3691TL-0.9 LM3691TLX–0.9 1.0* LM3691TL-1.0 LM3691TLX–1.0 1.1* LM3691TL-1.1 LM3691TLX–1.1 1.2 LM3691TL–1.2 LM3691TLX–1.2 1.3* LM3691TL–1.3 LM3691TLX–1.3 1.375* LM3691TL–1.375 LM3691TLX–1.375 1.5 LM3691TL–1.5 LM3691TLX– ...

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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. If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. V Pin ...

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Block Diagram FIGURE 3. Simplified Functional Diagram 5 30013431 www.national.com ...

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... T A noted. Quiescent Supply current vs. Supply Voltage No Switching (ECO Mode) Shutdown Current vs. Temp (V = 1.8V) OUT www.national.com LM3691TL Typical Application Circuit (page 1 4.7 μF, 0603(1608), 6.3V, (C1608X5R0J475K) unless otherwise = C IN OUT Quiescent Supply current vs. Supply Voltage No Switching (PWM Mode) 30013455 Switching Frequency vs. Temp (V OUT ...

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Output Voltage vs. Supply Voltage (V = 0.75V) OUT 30013459 Output Voltage vs. Output Current (V = 0.75V) OUT 30013461 Input Current vs. Output Current (V = 0.75V) OUT 30013463 Output Voltage vs. Supply Voltage (V = 1.8V) OUT Output ...

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Efficiency vs. Output Current (V = 0.75V, ECO Mode) OUT Efficiency vs. Output Current (V = 0.75V, FPWM Mode) OUT Load Current Threshold vs. Supply Voltage (V = 0.75V, ECO Mode to PWM Mode) OUT www.national.com Efficiency vs. Output Current ...

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Output Voltage Ripple vs. Supply Voltage (V = 0.75V) OUT Closed Loop Current Limit vs. Temperature (V = 0.75V) OUT Line Transient Reponse (V = 0.75V, PWM Mode) OUT Output Voltage Ripple vs. Supply Voltage 30013471 Closed Loop Current Limit ...

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Load Transient Reponse (V = 0.75V, ECO Mode 1mA to 25 mA) OUT Load Transient Reponse (V = 1.8V, ECO Mode 1mA to 25 mA) OUT Load Transient Reponse (V = 0.75V, ECO Mode to PWM Mode) OUT www.national.com Load ...

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Load Transient Reponse (V = 1.8V, ECO Mode to PWM Mode) OUT Load Transient Reponse (V = 0.75V, FPWM Mode) OUT Load Transient Reponse (V = 1.8V, FPWM Mode) OUT Load Transient Reponse (V = 1.8V, PWM Mode to ECO ...

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Load Transient Reponse (V = 0.75V, PWM Mode) OUT Start Up into ECO Mode (V = 1.8V, R OUT OUT Start Up into ECO Mode (V = 0.75V, R OUT OUT www.national.com 30013491 = 1.8 kΩ) 30013493 = 750 Ω) ...

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Operation Description DEVICE INFORMATION The LM3691, a high-efficiency, step-down DC-DC switching buck converter, delivers a constant voltage from either a sin- gle Li-Ion or three cell NiMH/NiCd battery to portable devices such as cell phones and PDAs. Using a voltage ...

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FIGURE 5. Typical ECO Operation FORCED PWM MODE Setting Mode pin high (>1.2V) places the LM3691 in Forced PWM. The part is in forced PWM regardless of the load. SHUTDOWN MODE Setting the EN input pin low (<0.4V) places the ...

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Application Information INDUCTOR SELECTION DC bias current characteristics of inductors must be consid- ered. Different manufacturers follow different saturation cur- rent rating specifications, so attention must be given to details. DC bias curves should be requested from them as part ...

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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 ...

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Physical Dimensions inches (millimeters) unless otherwise noted 6–bump Thin Micro SMD, Large Bump NS Package Number TLA06LCA X1 = 1.260mm ± 0.030mm X2 = 1.565mm ± 0.030mm X3 = 0.600mm ± 0.075mm 17 www.national.com ...

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