Conclusion

AN2811

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Doc ID 14904 Rev 1

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Conclusion

This document introduces a non-isolated offline constant-current LED driver based on the

VIPer17. The input range is 220 VAC +/- 20% and the device is capable of driving two

500 mA white light LEDs. The LED current is sensed and regulated through the TSM103W

and attains a constant output current. By using resistors with 1% precision, the output

current achieves a maximum tolerance less than 5%. The input fuse and input filter are built

on a 30 mm x 30 mm PCB. Overtemperature protection, LED open-circuit and LED short-

circuit protection are all integrated functions which enhance the reliability of the device.