LM20242MH/NOPB National Semiconductor, LM20242MH/NOPB Datasheet
LM20242MH/NOPB
Specifications of LM20242MH/NOPB
LM20242MH
Related parts for LM20242MH/NOPB
LM20242MH/NOPB Summary of contents
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... The LM20242 is offered in an exposed pad 20 pin TSSOP 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. © 2008 National Semiconductor Corporation ® Adjustable Frequency Synchronous Features ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20242MH eTSSOP-20 LM20242MHE LM20242MHX 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, 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 Current Limit LIM T Cycle By Cycle Current Limit Delay ILIM Enable V EN Pin Rising Threshold EN(RISING Pin Hysteresis EN(HYS Source Current EN Thermal Shutdown T Thermal ...
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Error Amplifier Gain 30031405 Line Regulation 30031407 Non-Switching I vs 30031409 Error Amplifier Phase V vs Shutdown I vs 30031406 30031408 IN 30031410 www.national.com ...
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PGOOD V vs Current vs. Temperature Oscillator Frequency vs. V www.national.com EN Threshold and Hysteresis vs. Temperature PGOOD 30031419 30031422 High-Side FET Resistance vs. Temperature IN 30031454 6 30031421 Oscillator Frequency vs 30031453 30031455 ...
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Load Transient Response 30031456 Peak Current Limit vs. Temperature 30031458 Startup with C = 200 nF SS 30031460 Low-Side FET Resistance vs. Temperature Startup with 30031457 = 0 30031459 www.national.com ...
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Block Diagram www.national.com 8 30031423 ...
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Operation Description GENERAL The LM20242 switching regulator features all of the functions necessary to implement an efficient low voltage buck regula- tor using a minimum number of external components. This easy to use regulator features two integrated switches and is ...
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LM20242 tri-states the power FETs and resets soft-start. After the junction cools to approximately 150°C, the part starts up using the normal start up routine. This feature is provided to prevent catastrophic failures from accidental device over- heating. LIGHT LOAD ...
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Design Guide This section walks the designer through the steps necessary to select the external components to build a fully functional power supply. As with any DC-DC converter numerous trade- offs are possible to optimize the design for efficiency, size, ...
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The output voltage ripple can be approximated by using the following formula. Where, ΔV (V) is the amount of peak to peak voltage ripple OUT (Ω) is the series resistance at the power supply output, ...
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FIGURE 4. LM20242 Loop Compensation 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. ...
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If different start up times are needed the equation shown be- low can be used to calculate the start up time. As shown above, the start up time is influenced by the value of the soft-start capacitor C (F) and ...
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The second most common power on behavior is known as a ratiometric start up. This start up is preferred in applications where both supplies need the final value at the same time. Similar to the soft-start function, ...
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FIGURE 9. Schematic of LM20242 Highlighting Layout Sensitive Nodes www.national.com FIGURE 10. Typical Application Schematic 16 30031446 30031444 ...
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Bill of Materials ID Qty Part Number U1 1 LM20242MH L1 1 MSS1260-153MX C1-3 3 GRM32ER71H475KA88L C4 VJ0805JY104KXX C5 VJ0805Y105JXACW1BC C7 1 C1608COG1H121J C8 1 VJ0805Y222J C10 1 C1210C107M9PAC D1 MBR0540 R1,9 2 ...
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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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