Texas Instruments LM3445 Evaluation Board LM3445-120VFLBK/NOPB LM3445-120VFLBK/NOPB Benutzerhandbuch
Produktcode
LM3445-120VFLBK/NOPB
Application Report
SNVA429C – August 2010 – Revised May 2013
AN-2034 LM3445 -120VAC, 8W Isolated Flyback
LED Driver
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ABSTRACT
This demonstration board highlights the performance of a LM3445 based Flyback LED driver solution that
can be used to power a single LED string consisting of 4 to 8 series connected LEDs from an 90 V
can be used to power a single LED string consisting of 4 to 8 series connected LEDs from an 90 V
RMS
to
135 V
RMS
, 60 Hz input power supply. The key performance characteristics under typical operating
conditions are summarized in this application report.
Contents
1
Introduction
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2
Key Features
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3
Applications
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4
Performance Specifications
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5
LM3445 120VAC, 8W Isolated Flyback LED Driver Demo Board Schematic
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6
LM3445 Device Pin-Out
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7
Bill of Materials
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8
Demo Board Wiring Overview
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9
Demo Board Assembly
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10
Typical Performance Characteristics
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11
PCB Layout
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12
Transformer Design
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13
Experimental Results
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13.1
Non-Dimming Performance
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13.2
Dimming Performance
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13.3
Power Factor Performance
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14
Circuit Operation With Rotary Forward Phase TRIAC Dimmer
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15
Circuit Operation With Reverse Phase TRIAC Dimmer
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16
Electromagnetic Interference (EMI)
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17
Thermal Analysis
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18
Circuit Analysis and Explanations
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18.1
Injecting Line Voltage into Filter-2 (Achieving PFC > 0.95)
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List of Figures
1
Demo Board
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2
LED Current vs. Input Voltage (using Dimmer)
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3
Demo Board Schematic
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4
LM3445 Device Pin-Out
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5
Wiring Connection Diagram
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6
Top View
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7
Bottom View
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8
Efficiency vs. Line Voltage Original Circuit
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9
Efficiency vs. Line Voltage Modified Circuits
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10
LED Current vs. Line Voltage Original Circuit
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1
SNVA429C – August 2010 – Revised May 2013
AN-2034 LM3445 -120VAC, 8W Isolated Flyback LED Driver
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