LM20146MH/NOPB National Semiconductor, LM20146MH/NOPB Datasheet
LM20146MH/NOPB
Specifications of LM20146MH/NOPB
Related parts for LM20146MH/NOPB
LM20146MH/NOPB Summary of contents
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... The LM20146 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. © 2009 National Semiconductor Corporation LM20146 Features ■ Input voltage range 2.95V to 5.5V ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM20146MH eTSSOP-16 LM20146MHE LM20146MHX 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, 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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Error Amplifier Gain vs. Frequency Load Regulation Switching Frequency vs. Temperature (T Line Regulation 30053836 Feedback Pin Voltage vs. Temperature (T 30053838 ) Switching Frequency vs 30053839 5 30053837 ) J 30053851 T 30053850 www.national.com ...
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Quiescent Current vs. V Enable Threshold vs. Temperature (T Peak Current Limit vs. Temperature (T www.national.com (Not Switching) IN 30053840 ) J 30053828 ) J 30053867 6 Shutdown Current vs. Temperature (T 30053841 UVLO Threshold vs. Temperature (T 30053845 Peak ...
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Peak Current Limit vs 30053863 Line Transient Response 30053843 Start-Up (Tracking) 30053833 Load Transient Response Start-Up (Soft-Start) Power Down 7 30053834 30053844 30053832 www.national.com ...
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Short Circuit Input Current vs. V www.national.com P IN 30053856 8 vs. I GOOD PGOOD 30053827 ...
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Block Diagram 9 30053803 www.national.com ...
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Operation Description GENERAL The LM20146 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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UVLO The LM20146 has a built-in under-voltage lockout protection circuit that keeps the device from switching until the input voltage reaches 2.7V (typical). The UVLO threshold has hysteresis that keeps the device from responding to power-on glitches ...
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FIGURE 2. Modes of Operation for LM20146 12 30053805 ...
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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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FIGURE 5. LM20146 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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As shown above, the start up time is influenced by the value of the Soft-Start capacitor C (F) and the 5 µA Soft-Start pin SS current I (A). SS While the Soft-Start capacitor can be sized to meet many start ...
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Similar to the Soft-Start function, the fastest start up possible is 1ms regardless of the rise time of the tracking voltage. When using the track feature the final voltage seen by the SS/ TRACK pin should exceed 1V to provide ...
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FIGURE 11. Schematic of LM20146 Highlighting Layout Sensitive Nodes www.national.com 30053822 18 ...
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... I OUT SW Part Number LM20146 C3225X5R0J107M C3225X5R0J107M SPM6530T-1R0M120 CRCW06031R0J-e3 GRM188R71C104KA01 GRM188R60J105KA01 CRCW06031432F-e3 GRM1885C1H102JA01 VJ0603Y333KXXA CRCW06031003F-e3 CRCW06033162F-e3 CRCW06031022F-e3 19 and C1 as outlined in the design C1 30053860 = 6A) OUTMAX Manufacturer Qty National Semiconductor 1 TDK 1 TDK 1 TDK 1 Vishay-Dale 1 Murata 1 Murata 1 Vishay-Dale 1 Murata 1 Vishay-Vitramon 1 Vishay-Dale 1 Vishay-Dale 1 Vishay-Dale 1 www.national.com ...
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... X7R, 25V SS 48.7kΩ, 0603 R T 4.99kΩ, 0603 R FB1 10kΩ, 0603 R FB2 www.national.com = 1.2V, F =750kHz, I OUT SW Part Number Manufacturer LM20146 National Semiconductor C3225X5R0J107M C3225X5R0J107M SPM6530T-R68M140 CRCW06031R0J-e3 Vishay-Dale GRM188R71C104KA01 GRM188R60J105KA01 CRCW06034532F-e3 Vishay-Dale VJ0603Y182KXXA Vishay-Vitramon VJ0603Y333KXXA Vishay-Vitramon CRCW06034872F-e3 Vishay-Dale CRCW06034991F-e3 Vishay-Dale CRCW06031002F-e3 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 16-Lead eTSSOP Package NS Package Number MXA16A 21 www.national.com ...
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