LM5008ASD/NOPB National Semiconductor, LM5008ASD/NOPB Datasheet
LM5008ASD/NOPB
Specifications of LM5008ASD/NOPB
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LM5008ASD/NOPB Summary of contents
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... Other fea- tures include: Thermal Shutdown, V Gate drive under-voltage lockout, Max Duty Cycle limiter, and a pre-charge switch. Typical Application, Basic Step-Down Regulator © 2009 National Semiconductor Corporation LM5008A Features ■ Operating input voltage range 95V ■ ...
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Connection Diagrams Top View 8-Lead LLP Ordering Information Order Number LM5008AMM LM5008AMMX LM5008ASD LM5008ASDX Pin Descriptions Pin Name Description 1 SW Switching Node 2 BST Boost Pin (Boot–strap capacitor input) 3 RCL Current Limit OFF time set pin 4 RTN ...
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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 apply over full Operating Junction Temperature range. V ...
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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 Efficiency vs. Load Current and V (Circuit of Figure 4) ON-Time vs Input Voltage and R Maximum Frequency vs 30074924 Current Limit Off-Time vs 30074925 and V I OUT IN CC 30074926 5 ...
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Block Diagram Functional Description The LM5008A Step Down Switching Regulator features all the functions needed to implement a low cost, efficient, Buck bias power converter. This high voltage regulator contains a 100 V N-Channel Buck Switch, is easy to implement ...
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The LM5008A regulates the output voltage based on ripple voltage at the feedback input, requiring a minimum amount of ESR for the output capacitor C2. A minimum of 25mV to 50mV of ripple voltage at the feedback pin (FB) is ...
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Regulation Comparator The feedback voltage compared to an internal 2.5V reference. In normal operation (the output voltage is regulat- ed), an on-time period is initiated when the voltage at FB falls below 2.5V. The buck switch will ...
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FIGURE 3. Shutdown Implementation Current Limit The LM5008A contains an intelligent current limit OFF timer. If the current in the Buck switch exceeds 0.51A the present cycle is immediately terminated, and a non-resetable OFF timer is initiated. The length of ...
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LM5008A’s current limit threshold (610 mA) with- out saturating, since the current limit is reached during start- up. The ...
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... Kemet C1206C103K5RAC TDK C3216X7R2A104M Diodes Inc. DFLS1100 COILTRONICS DR125-221-R, or TDK SLF10145T-221MR65 Vishay CRCW12063011F Vishay CRCW12061001F Vishay CRCW12063R00F Vishay CRCW12063243F Vishay CRCW12063323F National Semiconductor LM5008A 11 30074918 Value 1 µF, 100V 22 µF, 25V 0.47 µF, 50V 0.01 µF, 50V 0.1 µF, 100V 100V, 1A 220 µH 3.01 kΩ ...
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LOW OUTPUT RIPPLE CONFIGURATIONS For applications where low output ripple is required, the fol- lowing options can be used to reduce or nearly eliminate the ripple. a) Reduced ripple configuration: In Figure 7, Cff is added across R to AC-couple ...
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FIGURE 7. Reduced Ripple Configuration b) Minimum ripple configuration: If the application requires a lower value of ripple (<10 mVp-p), the circuit of Figure 8 can be used removed, and the resulting output ripple volt- age is determined ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 8-Lead MSOP Package NS Package Number MUA08A 8-Lead LLP Package NS Package Number SDC08B 14 ...
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