LM34910EVAL National Semiconductor, LM34910EVAL Datasheet
LM34910EVAL
Specifications of LM34910EVAL
Related parts for LM34910EVAL
LM34910EVAL Summary of contents
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... Order Number Package Type LM34910SD LLP-10 (4x4) LM34910SDX LLP-10 (4x4) © 2005 National Semiconductor Corporation n Ultra-Fast transient response n Operating frequency remains constant with load current and input voltage n Maximum Duty Cycle Limited During Start-Up n Adjustable output voltage n Valley Current Limit At 1.25A ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 1. 2 20110901 ...
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Pin Description 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 type apply over full Operating Junction Temperature range. V ...
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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 LM34910 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 40V N-Channel buck switch, ...
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Start-up Regulator The start-up regulator is integral to the LM34910. The input pin (V ) can be connected directly to line voltage up to 36V, IN with transient capability to 40V. The V CC 7.0V, and is current ...
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ON-Time Timer, and Shutdown (Continued) FIGURE 6. Shutdown Implementation Current Limit Current limit detection occurs during the off-time by monitor- ing the recirculating current through the free-wheeling diode FIGURE 7. Inductor Current - Current Limit Operation The current limit threshold ...
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Thermal Shutdown The LM34910 should be operated so the junction tempera- ture does not exceed 125˚C. If the junction temperature increases, an internal Thermal Shutdown circuit, which acti- vates (typically) at 175˚C, takes the controller to a low power reset ...
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Applications Information C4: The recommended value for C4 is 0.022 µF. A high quality ceramic capacitor with low ESR is recommended as C4 supplies a surge current to charge the buck switch gate at turn-on. A low ESR also helps ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor manufactures products and uses packing materials that 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. ...