I designed a dental curing light using a Lumiled LED. It's running about
7V at 1.5A (copper heat sink with excellent bonding to the heat sink). I
used an LTC boost converter (the unit runs on a lithium ion battery). I
used a Maxim current sense amplifier to do a high side current sense of
the current going into the LED. The output of the amplifier goes to the
voltage feedback input of the LTC part. Many thousand have shipped! One
trick with boost converters is that the minimum output voltage is the
input voltage minus one voltage drop. This, however, was less than the
forward voltage of the LED, so no additional switching was required.

Harold


> Definitely. Check out the Lumileds website for application notes and
> links to some people who have developed specialized drivers for the
> Luxeon series.
>
> Josh
> --
> A common mistake that people make when trying to design something
> completely foolproof is to underestimate the ingenuity of complete
> fools.
>         -Douglas Adams
>
> On 9/24/05, mrgizmo <mrgizmo@vianet.ca> wrote:
>>   Is there any way to drive a 3 W luxeon star without using a huge power
>> risistor. 3.7V at 700ma or 3.9V at 1000ma.
>
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