SSL3401HN Datasheet, PDF (14/29 Pages) NXP Semiconductors – Low voltage dimmable controller for LED lighting

NXP Semiconductors
SSL3401HN
Low voltage dimmable controller for LED lighting
8.9 LED selection
The LED forward voltage is crucial to obtaining the full dimmer and transformer
compatibility performance. An LED voltage that is too low may cause transient short
between the input voltage and the boost output voltage, which affects the light stability.
Use an LED with a typical forward voltage of > 26.6 V, at the actual application maximum
LED current and an LED junction temperature of 80 C. This same minimum LED voltage
limit becomes 27.7 V if the measurement point is a junction temperature of 25 C.
Included in the calculation are:
• Temperature derating
• Aging effect
• V_f spread = 10 %
• Mains voltage variation = +10 %
• Transformer output voltage spread = +10 %
Only the application component rating and/or thermal dissipation constraints determine
the LED voltage upper limit.
SSL3401HN
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 28 January 2014
© NXP B.V. 2014. All rights reserved.
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