lm5008mmep National Semiconductor Corporation, lm5008mmep Datasheet
lm5008mmep
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lm5008mmep Summary of contents
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... Enhanced Diminishing Manufacturing Sources (DMS) Support Ordering Information PART NUMBER LM5008MMEP (Notes 1, 2) Note 1: For the following (Enhanced Plastic) version, check for availability: - LM5008MMXEP, LM5008SDEP, LM5008SDXEP. Note 2: FOR ADDITIONAL ORDERING AND PRODUCT INFORMATION, PLEASE VISIT THE ENHANCED PLASTIC WEB SITE AT: www.national.com/mil ...
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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 -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 8) Human Body Model ...
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Electrical Characteristics Specifications with standard typeface are for T Temperature range 48V, unless otherwise stated (Note 6). IN Symbol Parameter Minimum Off Time Minimum Off Timer Regulation and OV Comparators FB Reference Threshold FB Over-Voltage Threshold FB Bias ...
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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 20187609 Voltage FIGURE 4. Maximum Frequency 20187610 FIGURE 5. Current Limit Off-Time 20187611 ...
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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 20187623 Functional Description IN The LM5008EP 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 LM5008EP 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 ...
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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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Applications Information Item Description C1 Ceramic Capacitor C2 Ceramic Capacitor C3 Ceramic Capacitor C4 Ceramic Capacitor C5 Ceramic Capacitor D1 UltraFast Power Diode L1 Power Inductor R1 Resistor R2 Resistor R3 Resistor R Resistor ON R Resistor CL U1 Switching ...
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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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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry ...