LM5008MM/NOPB National Semiconductor, LM5008MM/NOPB Datasheet
LM5008MM/NOPB
Specifications of LM5008MM/NOPB
LM5008MMTR
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LM5008MM/NOPB Summary of contents
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... Max Duty Cycle limiter Connection Diagram Ordering Information Order Number LM5008MM LM5008MMX LM5008SD LM5008SDX LM5008SDC LM5008SDCX © 2009 National Semiconductor Corporation LM5008 Features ■ Integrated 100V, N-Channel buck switch ■ Internal V ■ No loop compensation required ■ Ultra-Fast transient response ■ ...
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Typical Application Circuit and Block Diagram www.national.com 2 ...
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Pin Descriptions Pin Name 1 SW Switching Node 2 BST Boost Pin (Boot–strap capacitor input Current Limit OFF time set pin CL Toff = (0.285 + ( RTN Ground pin ...
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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 GND IN BST to GND SW to GND (Steady State) ESD Rating (Note 5) Human Body Model BST Electrical Characteristics Specifications with standard typeface are for T perature range ...
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... Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: For detailed information on soldering plastic MSOP and LLP packages, refer to the Packaging Data Book available from National Semiconductor Corporation. ...
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Typical Performance Characteristics FIGURE 2. I Current vs Applied V CC FIGURE 3. ON-Time vs Input Voltage and R FIGURE 4. Maximum Frequency vs V www.national.com 20097909 FIGURE 5. Current Limit Off-Time vs V Voltage CC 20097910 ON 20097911 and ...
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FIGURE 7. Efficiency vs Load Current vs V (Circuit of Figure 13) Functional Description The LM5008 Step Down Switching Regulator features all the functions needed to implement a low cost, efficient, Buck bias power converter. This high voltage regulator contains ...
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High Voltage Start-Up Regulator The LM5008 contains an internal high voltage startup regu- lator. The input pin (V ) can be connected directly to the line IN voltages Volts, with transient capability to 100 volts. The regulator ...
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On-Time Generator and Shutdown The on-time for the LM5008 is determined by the R and is inversely proportional to the input voltage (Vin), result- ing in a nearly constant frequency as Vin is varied over its range. The on-time equation ...
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The maximum allowed frequency, based on a minimum on-time of 400 ns, is calculated from MAX OUT INMAX For this exercise, Fmax = 263kHz. From equation 1, R culates to 304 kΩ. ...
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R : When a current limit condition is detected, the minimum CL off-time set by this resistor must be greater than the maximum normal off-time which occurs at maximum Vin. Using equation 2, the minimum on-time is 0.470 µs, yielding ...
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... Kemet C1206C104K5RAC Kemet C1206C103K5RAC TDK C3216X7R2A104M ON Semi MURA110T3 Coilcraft DO3316-224 or TDK SLF10145T-221MR65 Vishay CRCW12063011F Vishay CRCW12061001F Vishay CRCW12062R00F Vishay CRCW12063573F Vishay CRCW12062673F National Semiconductor LM5008 12 20097922 Value 1µF, 100V 15µF, 25V 0.1µF, 50V 0.01µF, 50V 0.1µF, 100V 100V, 1A 220 µ ...
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Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead MSOP Package NS Package Number MUA08A 8-Lead LLP Package NS Package Number SDC08A 13 www.national.com ...
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LLP Package NS Package Number SDC08B 14 ...
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Notes 15 www.national.com ...
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