E
Emtech
- Jan 1, 1970
- 0
Hi
I am playing with an RGB LED to mix colours with PWM of each component. I
also
want to change the brightness of the combined (mixed) colour without
changing the
selected colour (i.e. selected by the PWM combination). Later I want to add
up to 16
RGB LEDs.
For the brightness control what are your thoughts on the following ideas
(cheap & simple):
1. LM317 for the LED supply adjusted with a digital pot via the uP.
(Limited, range but useful)
2. Using an individual current sources, one for each colour. Something like
the Fairchild
FAN5612 with a PWM DAC to control the selected current.
3. Any other ideas?
Thanks...
John..
I am playing with an RGB LED to mix colours with PWM of each component. I
also
want to change the brightness of the combined (mixed) colour without
changing the
selected colour (i.e. selected by the PWM combination). Later I want to add
up to 16
RGB LEDs.
For the brightness control what are your thoughts on the following ideas
(cheap & simple):
1. LM317 for the LED supply adjusted with a digital pot via the uP.
(Limited, range but useful)
2. Using an individual current sources, one for each colour. Something like
the Fairchild
FAN5612 with a PWM DAC to control the selected current.
3. Any other ideas?
Thanks...
John..