[sdiy] MIDI/CV sync LED lit plastic panel?

[Brock Russell]

>my question wasnt about MIDI/CV converters, it was
>about translating the CV to the LEDs intensity.  it
>seems like it should be a simple thing!
>
>denshi

Driving the LEDs with a pulse width modulator will
give you the best control. You can use something
as simple as a 555 timer.
Best results can probably be achieved by setting the
frequency to around 1 kHz, LED drive current to 15 to
25mA, (depending on the LEDs used),  and varying the
pulse width between 0 and 100% will give a very linear
output.

There are other techniques that will work such as a
voltage controlled current source or driving the sense
pin of a constant current LED driver such as the
Allegro A6275 but you won't get the range or linearity
that can be obtained with PWM.

Brock