Manuali utente per Texas Instruments LM3404 Evaluation Boards LM3404HVEVAL/NOPB

Sommario

• FEATURES

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• APPLICATIONS

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• DESCRIPTION

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  • Typical Application

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  • Connection Diagrams

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• ABSOLUTE MAXIMUM RATINGS(LM3404)

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• RECOMMENDED OPERATING CONDITIONS (LM3404)

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• ABSOLUTE MAXIMUM RATINGS (LM3404HV)

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• RECOMMENDED OPERATING CONDITIONS (LM3404HV)

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• ELECTRICAL CHARACTERISTICS

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• LM3404

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• LM3404HV

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• LM3404/LM3404HV

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• TYPICAL PERFORMANCE CHARACTERISTICS

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• BLOCK DIAGRAM

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• APPLICATION INFORMATION

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  • THEORY OF OPERATION

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  • CONTROLLED ON-TIME OVERVIEW

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  • AVERAGE LED CURRENT ACCURACY

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  • MAXIMUM OUTPUT VOLTAGE

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  • MINIMUM OUTPUT VOLTAGE

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  • HIGH VOLTAGE BIAS REGULATOR

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  • INTERNAL MOSFET AND DRIVER

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  • FAST SHUTDOWN FOR PWM DIMMING

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  • PEAK CURRENT LIMIT

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  • OVER-VOLTAGE/OVER-CURRENT COMPARATOR

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  • LOW POWER SHUTDOWN

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  • THERMAL SHUTDOWN

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• DESIGN CONSIDERATIONS

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  • SWITCHING FREQUENCY

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  • LED RIPPLE CURRENT

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  • BUCK CONVERTERS WITHOUT OUTPUT CAPACITORS

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  • BUCK CONVERTERS WITH OUTPUT CAPACITORS

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  • INPUT CAPACITORS

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  • RECIRCULATING DIODE

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  • LED CURRENT DURING DIM MODE

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  • TRANSIENT PROTECTION CONSIDERATIONS

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    • CS PIN PROTECTION

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    • CS PIN PROTECTION WITH OVP

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    • VIN PIN PROTECTION

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    • GENERAL COMMENTS REGARDING OTHER PINS

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  • Design Example 1: LM3404

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    • RON and tON

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    • OUTPUT INDUCTOR

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    • USING AN OUTPUT CAPACITOR

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    • RSNS

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    • INPUT CAPACITOR

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    • RECIRCULATING DIODE

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    • CB AND CF

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    • EFFICIENCY

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  • Design Example 2: LM3404HV

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    • RON and tON

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    • OUTPUT INDUCTOR

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    • USING AN OUTPUT CAPACITOR

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    • RSNS

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    • INPUT CAPACITOR

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    • RECIRCULATING DIODE

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    • CB AND CF

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    • EFFICIENCY

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  • Layout Considerations

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    • COMPACT LAYOUT

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    • GROUND PLANE AND SHAPE ROUTING

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    • CURRENT SENSING

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    • REMOTE LED ARRAYS

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• Revision History

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