LM20323EVAL National Semiconductor, LM20323EVAL Datasheet
LM20323EVAL
Specifications of LM20323EVAL
Related parts for LM20323EVAL
LM20323EVAL Summary of contents
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... The LM20323 is offered in an exposed pad 20-pin eTSSOP package that can be soldered to the PCB, eliminating the need for bulky heatsinks. Simplified Application Circuit ® PowerWise is a registered trademark of National Semiconductor Corporation. © 2009 National Semiconductor Corporation Features ■ 4.5V to 36V input voltage range ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20323MH eTSSOP-20 LM20323MHE LM20323MHX Pin Descriptions Pin(s) Name Description 1 SS/TRK Soft-Start or Tracking control input 2 FB Feedback input to the error amplifier from the regulated output 3 PGOOD Power good ...
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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 GND BOOT to GND BOOT GND SW to GND (Transient) FB, EN, SS/TRK, COMP, PGOOD to GND Electrical Characteristics type are for T = 25°C only, limits in bold face type apply over the junction temperature (T J and maximum limits are guaranteed through test, design, or statistical correlation ...
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Symbol Parameter Current Limit I Cycle By Cycle Positive Current Limit LIM I Cycle By Cycle Negative Current Limit LIMNEG T Cycle By Cycle Current Limit Delay ILIM Enable V EN Pin Rising Threshold IH_EN V EN Pin Hysteresis EN(HYS) ...
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Error Amplifier Phase 30051506 Load Regulation 30051586 Non-Switching I vs 30051509 Line Regulation V vs Shutdown I vs 30051507 30051508 IN 30051510 www.national.com ...
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PGOOD Output Low Level Voltage vs. I UVLO Threshold and Hysteresis vs. Temperature Oscillator Frequency vs. V www.national.com Enable Threshold and Hysteresis vs. Temperature PGOOD 30051519 Enable Current vs. Temperature 30051595 High-Side FET Resistance vs. Temperature IN 30051554 6 30051521 ...
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Load Transient Response 30051556 Peak Current Limit vs. Temperature 30051558 Startup with 30051559 Low-Side FET Resistance vs. Temperature Startup with Prebiased Output Startup with C = 100 30051557 30051579 30051560 www.national.com ...
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Startup with Applied Track Signal www.national.com 30051581 8 ...
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Block Diagram 9 30051523 www.national.com ...
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Operation Description GENERAL The LM20323 switching regulator features all of the functions necessary to implement an efficient buck regulator using a minimum number of external components. This easy to use regulator features two integrated switches and is capable of supplying ...
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This feature is provided to prevent catastrophic failures from accidental device over- heating. Design Guide This section walks the designer through the steps necessary ...
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C (F) is the minimum required output capacitance, OUT L (H) is the value of the inductor, V voltage drop ignoring loop bandwidth considerations, ΔI (A) is the load step change, R STEP capacitor ESR, V (V) is the ...
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The power stage transfer function is dictated by the modula- tor, output LC filter, and load; while the feedback transfer function is set by the feedback resistor ratio, error amp gain and external compensation network. To achieve a -20dB/decade slope, ...
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The value for resistor R can be selected by the user to control B the current through the divider. Typically this resistor will be selected to be between 1 kΩ and 49.9 kΩ. Once the value for R is chosen ...
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MOSFET body diode and eliminating re- verse recovery losses. The external Schottky conducts currents for a very small por- tion of the switching cycle, therefore the average current is low. An external Schottky rated for 1A will improve ...
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FIGURE 10. Thermal Resistance vs PCB Area (4 Layer Board) PCB LAYOUT CONSIDERATIONS PC board layout is an important part of DC-DC converter de- sign. Poor board layout can disrupt the performance of a DC- DC converter and surrounding circuitry ...
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Bill of Materials (V = 12V Qty Part Number U1 1 LM20323MH C1 1 C3225X5R1E226M C2 GRM21BR61E475KA12L C5 C1608X7R1H104K C4 1 C1608X5R1A105K C7 1 C1608C0G1H100J C8 1 C1608C0G1H102J C9 1 6TPB150MAZB D1 1 ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 20-Lead eTSSOP Package NS Package Number MXA20A 18 ...
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Notes 19 www.national.com ...
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