LM20144MH/NOPB National Semiconductor, LM20144MH/NOPB Datasheet
LM20144MH/NOPB
Specifications of LM20144MH/NOPB
LM20144MH
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LM20144MH/NOPB Summary of contents
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... The LM20144 is offered in a 16-pin eTSSOP package with an exposed pad that can be soldered to the PCB, eliminating the need for bulky heatsinks. Typical Application Circuit ® PowerWise is a registered trademark of National Semiconductor Corporation. © 2008 National Semiconductor Corporation Adjustable Frequency Synchronous Buck Features ■ Input voltage range 2.95V to 5.5V ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20144MH eTSSOP-16 LM20144MHE LM20144MHX Pin Descriptions Pin # Name 1 SS/TRK Soft-Start or Tracking control input. An internal 5 µA current source charges an external capacitor to set the Soft-Start ramp rate. ...
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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. Voltages from the indicated pins to GND AVIN, PVIN, EN, PGOOD, SS/ TRK, COMP, FB, SW, RT Storage Temperature Junction Temperature Electrical Characteristics Limits in standard type are for T = 25° ...
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Symbol Parameter Enable V EN Pin turn-on Threshold IH_EN V EN Pin Hysteresis EN_HYS Thermal Shutdown T Thermal Shutdown SD T Thermal Shutdown Hysteresis SD_HYS Thermal Resistance θ Junction to Ambient JA Note 1: Absolute Maximum Ratings indicate limits beyond ...
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High-Side FET Resistance vs. Temperature Error Amplifier Gain vs. Frequency Load Regulation Low-Side FET Resistance vs. Temperature 30030657 Line Regulation 30030636 Feedback Pin Voltage vs. Temperature 30030638 5 30030658 30030637 30030651 www.national.com ...
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Switching Frequency vs. Temperature Quiescent Current vs. V Enable Threshold vs. Temperature www.national.com 30030639 (Not Switching) IN 30030640 30030628 6 Switching Frequency vs 30030650 Shutdown Current vs. Temperature 30030641 UVLO Threshold vs. Temperature 30030645 ...
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Peak Current Limit vs. Temperature 30030642 Peak Current Limit vs 30030655 Line Transient Response 30030643 Peak Current Limit vs. V Load Transient Response Start-Up (Soft-Start) 7 OUT 30030654 30030634 30030644 www.national.com ...
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Start-Up (Tracking) Short Circuit Input Current vs. V www.national.com 30030633 P IN 30030656 8 Power Down 30030632 vs. I GOOD PGOOD 30030627 ...
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Block Diagram 9 30030603 www.national.com ...
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Operation Description GENERAL The LM20144 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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When activated, typically at 160°C, the LM20144 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 ...
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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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Where, C (F) is the minimum required output capacitance, OUT L (H) is the value of the inductor, V DROOP voltage drop ignoring loop bandwidth considerations, ΔI (A) is the load step change, R STEP ESR capacitor ESR, V (V) ...
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FIGURE 4. LM20144 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 10. Schematic of LM20144 Highlighting Layout Sensitive Nodes 17 30030622 www.national.com ...
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... C1 as outline in the design guide. C1 30030601 = 4A) OUTMAX Manufacturer Qty National Semiconductor 1 Murata 1 Murata 1 Coilcraft 1 Vishay-Dale 1 Murata 1 Murata 1 Vishay-Dale 1 Vishay-Vitramon 1 Vishay-Vitramon 1 Vishay-Dale 1 Vishay-Dale 1 Vishay-Dale 1 = 4A) OUTMAX Manufacturer Qty National Semiconductor 1 Murata 1 Murata 1 Coilcraft 1 Vishay-Dale 1 Murata 1 Murata 1 Vishay-Dale 1 Vishay-Vitramon 1 Vishay-Vitramon 1 Vishay-Dale 1 Vishay-Dale 1 Vishay-Dale 1 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 16-Lead eTSSOP Package NS Package Number MXA16A 19 www.national.com ...
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