LM34914EVAL National Semiconductor, LM34914EVAL Datasheet
LM34914EVAL
Specifications of LM34914EVAL
Related parts for LM34914EVAL
LM34914EVAL Summary of contents
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... Features ■ Input Voltage Range 40V ■ Integrated N-Channel buck switch Basic Step Down Regulator © 2007 National Semiconductor Corporation ■ Valley current limit varies with V excessive inductor current ■ On-time is reduced when in current limit ■ Integrated start-up regulator ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM34914 SD LLP-10 (3x3) LM34914 SDX LLP-10 (3x3) Pin Descriptions Pin Number Name 1 SW Switching Node 2 BST Boost pin for bootstrap capacitor 3 ISEN Current sense 4 SGND Sense Ground ...
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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. VIN to RTN BST to RTN SW to RTN (Steady State) BST to VCC VIN to SW BST to SW VCC to RTN SGND to RTN Electrical Characteristics junction temperature (T ) range of -40° ...
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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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Typical Performance Characteristics Unless otherwise specified the following conditions apply: T Typical Efficiency Performance Valley Current Limit Threshold vs 25°C J 20197329 ON-Time vs V 20197307 and V Voltage at the RON/SD Pin ...
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Input Shutdown and Operating Current Into V www.national.com IN 20197305 6 ...
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Typical Application Circuit and Block Diagram 7 www.national.com ...
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Functional Description The LM34914 Step Down Switching Regulator features all the functions needed to implement a low cost, efficient buck bias power converter capable of supplying at least 1.25A to the load. This high voltage regulator contains an N-Channel buck ...
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The minimum load current for continuous conduction mode is one-half the inductor’s ripple current am- plitude. The approximate operating frequency is calculated as follows: The buck switch duty cycle is equal to: In discontinuous conduction mode, where ...
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To further reduce the inductor’s peak current, the next cycle’s on-time is reduced by approximately 50% if the voltage below its threshold when the in- ductor current reduces to the current limit ...
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Minimum and maximum load current (I ) (max) - Switching Frequency ( and R2: These resistors set the output voltage. The ratio of these resistors is calculated from: R1/ /2.5V OUT R1 ...
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expected that the internal dissipation of the LM34914 will produce excessive junction temperatures during normal operation, good use of the PC board’s ground plane can help to dissipate heat. The exposed pad on the bottom of the ...
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Physical Dimensions inches (millimeters) unless otherwise noted 10-Lead LLP Package NS Package Number SDA10A 13 www.national.com ...
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