Driver for variable number of LEDs

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Hi all,

I am designing a LED driver for 20 LEDs of 3.5 V, using LinkSwitch-PH family. What happens if I wire less than 20 LEDs in the circuit? Will it work?
I will need the circuit to work with 4 to 20 LEDs, is this possible? I could not find information regarding this in the datasheet.
How can I know the variation margin allowable for the output voltage?


The range of output voltage it will operate in CC is in page 3 Figure 5 of the datasheet. The CC control region is when IFB is betwwen IFB(skip) and IFB(DCMAX). IFB is proportional to output voltage via the turns ratio of output and bias winding. As you change your load voltage, IFB changes, and if your IFB is in the CC region, then you will have CC in that output voltage.