Texas Instruments LM3429 Evaluation Boards LM3429BKBSTEVAL/NOPB 사용자 매뉴얼

차례

• Features

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• Applications

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• Description

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  • Typical Boost Application Circuit

    1
  • Connection Diagram

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• Absolute Maximum Ratings

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• Operating Conditions

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• Electrical Characteristics

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• Typical Performance Characteristics

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• Block Diagram

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• Theory of Operation

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  • CURRENT REGULATORS

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    • Buck

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    • Boost

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    • Buck-boost

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  • PREDICTIVE OFF-TIME (PRO) CONTROL

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  • SWITCHING FREQUENCY

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    • Buck (Constant Ripple vs. VIN)

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    • Buck (Constant Ripple vs. VO)

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    • Boost and Buck-boost

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  • AVERAGE LED CURRENT

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  • ANALOG DIMMING

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  • CURRENT SENSE/CURRENT LIMIT

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  • CONTROL LOOP COMPENSATION

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  • OUTPUT OVER-VOLTAGE LOCKOUT (OVLO)

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    • Ground Referenced

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    • Floating

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  • INPUT UNDER-VOLTAGE LOCKOUT (UVLO)

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    • UVLO only

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    • PWM dimming and UVLO

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  • PWM DIMMING

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  • STARTUP REGULATOR (VCC LDO)

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  • THERMAL SHUTDOWN

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• Design Considerations

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  • INDUCTOR

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  • LED DYNAMIC RESISTANCE (rD)

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  • OUTPUT CAPACITOR

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  • INPUT CAPACITORS

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  • N-CHANNEL MosFET (NFET)

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  • RE-CIRCULATING DIODE

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  • CIRCUIT LAYOUT

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  • Basic Topology Schematics

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    • BOOST REGULATOR (VIN < VO)

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    • BUCK REGULATOR (VIN > VO)

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    • BUCK-BOOST REGULATOR

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  • Design Guide

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    • SPECIFICATIONS

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    • 1. OPERATING POINT

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    • 2. SWITCHING FREQUENCY

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    • 3. AVERAGE LED CURRENT

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    • 4. INDUCTOR RIPPLE CURRENT

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    • 5. LED RIPPLE CURRENT

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    • 6. PEAK CURRENT LIMIT

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    • 7. LOOP COMPENSATION

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    • 8. INPUT CAPACITANCE

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    • 9. NFET

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    • 10. DIODE

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    • 11. OUTPUT OVLO

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    • 12. INPUT UVLO

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    • 13. PWM DIMMING METHOD

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    • 14. ANALOG DIMMING METHOD

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  • Design Example #1

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    • BUCK-BOOST APPLICATION - 6 LEDs at 1A

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    • SPECIFICATIONS

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    • 1. OPERATING POINT

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    • 2. SWITCHING FREQUENCY

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    • 3. AVERAGE LED CURRENT

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    • 4. INDUCTOR RIPPLE CURRENT

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    • 5. OUTPUT CAPACITANCE

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    • 6. PEAK CURRENT LIMIT

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    • 7. LOOP COMPENSATION

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    • 8. INPUT CAPACITANCE

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    • 9. NFET

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    • 10. DIODE

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    • 11. INPUT UVLO

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    • 12. OUTPUT OVLO

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    • Design #1 Bill of Materials

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• Applications Information

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  • DESIGN #2: BOOST PWM DIMMING APPLICATION - 9 LEDs at 1A

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  • Design #2 Bill of Materials

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  • DESIGN #3: BUCK-BOOST ANALOG DIMMING APPLICATION - 4 LEDs at 2A

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  • Design #3 Bill of Materials

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  • DESIGN #4: BOOST ANALOG DIMMING APPLICATION - 12 LEDs at 700mA

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  • Design #4 Bill of Materials

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  • DESIGN #5: BUCK-BOOST PWM DIMMING APPLICATION - 6 LEDs at 500mA

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  • Design #5 Bill of Materials

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  • DESIGN #6: BUCK APPLICATION - 3 LEDS AT 1.25A

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  • Design #6 Bill of Materials

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  • DESIGN #7: BUCK-BOOST THERMAL FOLDBACK APPLICATION - 8 LEDs at 2.5A

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  • Design #7 Bill of Materials

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  • DESIGN #8: SEPIC APPLICATION - 5 LEDs at 750mA

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  • Design #8 Bill of Materialslayout of National Data Sheet to TI format

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• Revision History

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