AN-2084 NSC

Document overview

  • Manufacturer or author: Provided By digicamel.com
  • PDF pages: 10

Technical content

vibration certified and rated for operation down to –55°C.

  • LMZ1420xEXT VIN = 6V to 42V
  • LMZ1420xEXT enable UVLO = 8V
  • LMZ1420xEXT VOUT = 3.3V
  • LMZ1200xEXT VIN = 4.5V to 20V
  • LMZ1200xEXT enable UVLO = 4.5V
  • LMZ1200xEXT VOUT = 1.8V
  • Operates at full load up to 80°C ambient at 12V input
  • θJA = 20°C / W, θJC = 1.9°C / W
  • Designed on four layers, all four layers are 1 oz. copper weight
  • The two internal ground planes are identical 62mil (.062”) thick of FR4 laminate material For additional circuit modifications refer to the Design Con- sideration section of the LMZ1420xEXT or LMZ1200xEXT data sheet. For negative output voltage connections see AN-2027. Additional Footprints Additional component mounting pads are available to exper- iment with alternative Cin and Cout combinations or a zener clamp on the enable input. See Figure 6 for corresponding schematic locations. 30131501

FIGURE 1. Evaluation Board Schematic

TABLE 1. LMZ1420xEXT Bill of Materials, VIN = 8V to 42V, VOUT = 3.3V, IOUT (MAX) = 3A / 2A / 1A TABLE 2. LMZ1200xEXT Bill of Materials, VIN = 4.5 to 20V, VOUT = 1.8V, IOUT (MAX) = 3A / 2A / 1A

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LMZ14203EXT Thermal Derating 30131515 LMZ12003EXT Thermal Derating 30131516 LMZ14202EXT Thermal Derating 30131524 LMZ12002EXT Thermal Derating 30131525 LMZ14201EXT Thermal Derating 30131526 LMZ12001EXT Thermal Derating 30131527 www.national.com 4 AN-2084

LMZ14203EXT Current Limit VOUT = 3.3V 30131528 LMZ12003EXT Current Limit VOUT = 1.8V 30131529 LMZ14202EXT Current LimitVOUT = 3.3V 30131530 LMZ12002EXT Current Limit VOUT = 1.8V 30131531 LMZ14201EXT Current Limit VOUT = 3.3V 30131532 LMZ12001EXT Current Limit VOUT = 1.8V 30131533 5 www.national.com AN-2084

Gerber and CAD files can be download from the LMZ14203EXT product folder. FIGURE 2. Top Layer

FIGURE 6. LMZ14203EXT PCB CAD package schematic

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AN-2084 LMZ1420xEXT / LMZ1200xEXT Evaluation Board For more National Semiconductor product information and proven design tools, visit the following Web sites at: www.national.com Products Design Support Amplifiers www.national.com/amplifiers WEBENCH® Tools www.national.com/webench Audio www.national.com/audio App Notes www.national.com/appnotes Clock and Timing www.national.com/timing Reference Designs www.national.com/refdesigns Data Converters www.national.com/adc Samples www.national.com/samples Interface www.national.com/interface Eval Boards www.national.com/evalboards LVDS www.national.com/lvds Packaging www.national.com/packaging Power Management www.national.com/power Green Compliance www.national.com/quality/green Switching Regulators www.national.com/switchers Distributors www.national.com/contacts LDOs www.national.com/ldo Quality and Reliability www.national.com/quality LED Lighting www.national.com/led Feedback/Support www.national.com/feedback Voltage References www.national.com/vref Design Made Easy www.national.com/easy PowerWise® Solutions www.national.com/powerwise Applications & Markets www.national.com/solutions Serial Digital Interface (SDI) www.national.com/sdi Mil/Aero www.national.com/milaero Temperature Sensors www.national.com/tempsensors SolarMagic™ www.national.com/solarmagic PLL/VCO www.national.com/wireless PowerWise® Design University www.national.com/training THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS, IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS DOCUMENT. TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS. EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness. National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. Copyright© 2010 National Semiconductor Corporation For the most current product information visit us at www.national.com National Semiconductor Americas Technical Support Center Email: support@nsc.com Tel: 1-800-272-9959 National Semiconductor Europe Technical Support Center Email: europe.support@nsc.com National Semiconductor Asia Pacific Technical Support Center Email: ap.support@nsc.com National Semiconductor Japan Technical Support Center Email: jpn.feedback@nsc.com www.national.com