LM34910CSD National Semiconductor, LM34910CSD Datasheet
LM34910CSD
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LM34910CSD Summary of contents
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... Connection Diagram Ordering Information Order Number Package Type LM34910CSD LLP-10 (4x4) LM34910CSDX LLP-10 (4x4) LM34910CSDE LLP-10 (4x4) © 2007 National Semiconductor Corporation ■ Operating frequency remains constant with load current and input voltage ■ Maximum Duty Cycle Limited During Start-Up ■ ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 1. 2 30023501 ...
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Pin Descriptions Pin Name 1 SW Switching Node 2 BST Boost pin for boot-strap capacitor 3 I Current sense input SEN 4 S Sense Ground GND 5 RTN Circuit Ground 6 FB Feedback 7 SS Softstart 8 R /SD On-time ...
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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 2) Human Body Model BST BST to SW Electrical Characteristics apply over full Operating Junction Temperature range ...
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... Device thermal limitations limit external loading CC Note 4: For detailed information on soldering plastic LLP packages, refer to the Packaging Data Book available from National Semiconductor Corporation. Note 5: Typical specifications represent the most likely parametric norm at 25°C operation. ...
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Functional Description The LM34910C Step Down Switching Regulator features all the functions needed to implement a low cost, efficient buck bias power converter capable of supplying 1.25A to the load. This high voltage regulator contains a 55V N-Channel buck switch, ...
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Softstart pin is released to allow the Softstart capacitor (C6) to charge up. The minimum input voltage is determined by the regulator’s dropout voltage, the V UVLO falling threshold ( CC the frequency. When V falls below the falling threshold ...
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I and through D1. If that current SEN exceeds 1.25A the current limit comparator output switches to delay the start of the next on-time period if the voltage below 2.5V. The next ...
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Equation 1 can be used to select specific frequency ON is desired as long as the above limitation is met. L1: The main parameter affected by the inductor is the output current ripple amplitude (I ). The ...
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PC board’s ground plane can help considerably to dissipate heat. The exposed pad on the bot- tom of the IC package can be soldered to a ground plane, and that plane should extend out from ...
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Physical Dimensions inches (millimeters) unless otherwise noted 10-Lead LLP Package NS Package Number SDC10A 11 www.national.com ...
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