LM20134MH National Semiconductor, LM20134MH Datasheet
LM20134MH
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LM20134MH Summary of contents
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... The LM20134 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. © 2007 National Semiconductor Corporation Synchronous Buck Regulator with Input Features ■ Input voltage range 2.95V to 5.5V ■ ...
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... Connection Diagram Ordering Information Order Number Package Type LM20134MH eTSSOP-16 LM20134MHE LM20134MHX 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. If driven by a external source less tan 800 mV, this pin overrides the internal reference that sets the output voltage ...
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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, SYNC 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 ...
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High-Side FET resistance vs. Temperature Error Amplifier Gain vs. Frequency Load Regulation Low-Side FET resistance vs. Temperature 30030452 Line Regulation 30030436 Feedback Pin Voltage vs. Temperature 30030438 5 30030453 30030437 30030451 www.national.com ...
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Switching Frequency vs. Temperature Quiescent Current vs. Temperature (Not Switching) Enable Threshold vs. Temperature www.national.com Switch Synchronization 30030439 Shutdown Current vs. V 30030440 UVLO Threshold vs. Temperature 30030428 6 30030460 IN 30030441 30030445 ...
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Peak Current Limit vs. Temperature 30030442 Peak Current Limit vs 30030455 Line Transient Response 30030443 Peak Current Limit vs. V Load Transient Response Start-Up (Soft-Start) 7 OUT 30030454 30030434 30030444 www.national.com ...
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Start-Up (Tracking) Short Circuit Input Current vs. V www.national.com 30030433 P IN 30030456 8 Power Down 30030432 vs. I GOOD PGOOD 30030427 ...
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Block Diagram 9 30030403 www.national.com ...
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Operation Description GENERAL The LM20134 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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Typical values for the PGOOD resistor are on the or- der of 100 kΩ or less. To avoid false tripping during transient glitches the PGOOD pin has 16 µs of built in deglitch time to both rising and ...
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FIGURE 1. Modes of Operation for LM20134 12 30030405 ...
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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 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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To achieve a -20dB/decade slope, the error amplifier zero, located should positioned to cancel the output filter Z(EA) pole ( additional error amp pole, located at f P(FIL) can be added to cancel the output ...
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FIGURE 6. Sequencing LM20134 with Precision Enable 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 10 kΩ and 1 MΩ. ...
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T is the ambient temperature in ° the output load current. OUT DCR is the inductor series resistance important to always keep the operating junction temper- ature (T ) below 125°C for reliable operation. If ...
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FIGURE 10. Schematic of LM20134 Highlighting Layout Sensitive Nodes www.national.com 30030422 18 ...
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... C1 30030401 = 750kHz) SYNC 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 750kHz) SYNC 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 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 16-Lead eTSSOP Package NS Package Number MXA16A 20 ...
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Notes 21 www.national.com ...
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