Jesse Lackey wrote:
> I missed the description of the LED backlight, if any, but if there is a
> dc/dc involved (say a boost to run several white LEDs in series
> constant-current), then that dc/dc is being PWMed to control dimming,
> and it very well could have a low max PWM frequency.
>

"constant-current" means there is a resistor in the feedback loop. You
can place, say, 4 resistors and switch them accordingly using your
PIC.
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