Fairchild FEB157-001 Test Results 4.1 Regulation Line Regulation, LED Current vs. Line Voltage

Page 12

www.fairchildsemi.com

4.Test Results 4.1 Regulation

4.1.1Line Regulation

This graph illustrates the regulation of the output current over line voltage for the three possible settings, 350mA, 700mA, and 1A.

LED Current (mA)

1200

1000

800

 

 

 

 

 

1 LED

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

600

 

 

 

 

 

2 LEDs

 

 

 

 

 

 

400

 

 

 

 

 

3 LEDs

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

200

0

 

 

90

120

270

Input Voltage (Vac)

Figure 7: LED Current vs. Line Voltage

© 2007 Fairchild Semiconductor

Page 12 of 17

Rev 1.1 April 2007

Image 12
Contents FEB157-001 User’s Guide Contents Introduction Product Description Circuit DescriptionOffline LED Driver and LED Assembly Jumper JP1/JP2 Status and LED Current JP1 Status Electrical Requirements Input Requirements Output RequirementsDesigned Solution 3.1 Schematic Transformer Bill of MaterialsRS1M Printed Circuit Board RTH1Silkscreen/Component Placement of Top Side Layer Test Results 4.1 Regulation Line Regulation LED Current vs. Line VoltageEfficiency Steady State Operation Steady State Waveforms at 90Vac with Three LEDs at 1AStart up Startup Profile at 90 Vac with Three LEDs at 1AFairchild Semiconductor 526692/7