LM5008MM National Semiconductor, LM5008MM Datasheet
LM5008MM
Specifications of LM5008MM
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LM5008MM Summary of contents
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... Other protection features include: Ther- mal Shutdown, V under-voltage lockout, Gate drive under- CC voltage lockout, and Max Duty Cycle limiter Connection Diagram Ordering Information Order Number Package Type LM5008MM MSOP-8 LM5008SD LLP-8 © 2004 National Semiconductor Corporation Features n Integrated 100V, N-Channel buck switch n Internal V CC ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 1. 2 20097901 ...
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Pin Description PIN NAME 1 SW Switching Node 2 BST Boost Pin (Boot–strap capacitor input Current Limit OFF time set pin CL -5 Toff = 10 / (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 Temperature 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 www.national.com 20097909 Voltage FIGURE 4. Maximum Frequency 20097910 FIGURE 5. Current Limit Off-Time 20097911 ...
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Typical Performance Characteristics (Continued) FIGURE 6. Efficiency vs V (Circuit of Figure 13) FIGURE 7. Efficiency vs Load Current vs V (Circuit of Figure 13) FIGURE 8. Output Voltage vs Load Current 20097923 Functional Description IN The LM5008 Step Down ...
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Hysteretic Control Circuit Overview (Continued) the end of the off-time. The next on-time period starts when the voltage at FB falls below the internal reference - until then the inductor current remains zero. In this mode the operating frequency is ...
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High Voltage Start-up Regulator Regulation Comparator The feedback voltage compared to an internal 2.5V reference. In normal operation (the output voltage is regu- lated), an on-time period is initiated when the voltage at FB falls below 2.5V. ...
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Current Limit The LM5008 contains an intelligent current limit OFF timer. If the current in the Buck switch exceeds 0.5A the present cycle is immediately terminated, and a non-resetable OFF timer is initiated. The length of off-time is controlled by ...
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Applications Information false triggering of the V UVLO at the buck switch on/off CC transitions. For this reason, C3 should be no smaller than 0.1 µF. C2, and R3: When selecting the output filter capacitor C2, the items to consider ...
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Applications Information supply this average load current during the maximum on- time. To keep the input voltage ripple to less than 2V (for this exercise), C1 calculates to: Quality ceramic capacitors in this value have a low ESR which adds ...
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... 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 13 Value 1µF, 100V 15µF, 25V 0.1µF, 50V 0.01µF, 50V 0.1µF, 100V 100V, 1A 220 µH 3.01 kΩ ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 8-Lead MSOP Package NS Package Number MUA08A 14 ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...