Manuali utente per Texas Instruments LM3445 Evaluation Board LM3445-230VFLBK/NOPB

Sommario

• FEATURES

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• APPLICATIONS

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• DESCRIPTION

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  • Typical LM3445 LED Driver Application Circuit

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  • Connection Diagram

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• ABSOLUTE MAXIMUM RATINGS

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• OPERATING CONDITIONS

  3
• ELECTRICAL CHARACTERISTICS

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• TYPICAL PERFORMANCE CHARACTERISTICS

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• SIMPLIFIED INTERNAL BLOCK DIAGRAM

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• APPLICATION INFORMATION

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  • FUNCTIONAL DESCRIPTION

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  • OVERVIEW OF PHASE CONTROL DIMMING

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• THEORY OF OPERATION

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  • SENSING THE RECTIFIED TRIAC WAVEFORM

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  • LM3445 LINE SENSING CIRCUITRY

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  • TRIAC HOLDING CURRENT RESISTOR

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  • ANGLE DETECT

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  • BLEEDER

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  • FLTR1 PIN

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  • DIM DECODER

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  • VALLEY-FILL CIRCUIT

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  • VALLEY-FILL OPERATION

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  • BUCK CONVERTER

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  • OVERVIEW OF CONSTANT OFF-TIME CONTROL

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  • MASTER/SLAVE OPERATION

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  • MASTER/SLAVE CONFIGURATION

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  • MASTER BOARD MODIFICATIONS

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  • SLAVE BOARD(S) MODIFICATIONS

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  • MASTER/SLAVE(S) INTERCONNECTION

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  • MASTER/SLAVE THEORY OF OPERATION

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  • MASTER/SLAVE CONNECTION DIAGRAM

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  • MASTER/SLAVE BLOCK DIAGRAMS

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  • THERMAL SHUTDOWN

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• DESIGN GUIDE

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  • DETERMINING DUTY-CYCLE (D)

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  • CALCULATING OFF-TIME

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  • SETTING THE SWITCHING FREQUENCY

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  • INDUCTOR SELECTION

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  • SETTING THE LED CURRENT

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  • VALLEY FILL CAPACITORS

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    • Determining the capacitance value of the valley-fill capacitors

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    • Determining Maximum Number of Series Connected LEDs Allowed

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  • OUTPUT CAPACITOR

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  • SWITCHING MOSFET

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  • RE-CIRCULATING DIODE

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• DESIGN EXAMPLE

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• LM3445 DESIGN EXAMPLE 1 INPUT = 90VAC TO 135VAC, VLED = 7 x HB LED STRING APPLICATION @ 400 MA

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• Revision History

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