How to dim 16x32 RGB display
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- scott216
- Posts: 163
- Joined: Sun Apr 12, 2009 11:08 am
How to dim 16x32 RGB display
I'd like to dim the brightness of two 16x32 RGB LED displays using an analog output pin from an Arduino Mega. Initially, I was thinking of getting a voltage regulator chip where I could adjust the voltage, but that might not play nice with a PWM output from the Arduino. Now I'm thinking a transistor might be best, maybe a MOSFET. I'd appreciate any recommendations.
- adafruit_support_mike
- Posts: 67446
- Joined: Thu Feb 11, 2010 2:51 pm
Re: How to dim 16x32 RGB display
There's no practical way to control the brightness of an entire LED matrix with a single input. The amount of current used at any instant depends on the number of LEDs lit at that moment, and there's no guarantee that "50% power" would be distributed among all the LEDs equally.
To dim the LEDs, lower the PWM duty cycle for each one. You can create a single function to do that (our NeoPixel library's setBrightness() function applies a rather elegant gamma correction), but you need to handle the issue one LED at a time.
To dim the LEDs, lower the PWM duty cycle for each one. You can create a single function to do that (our NeoPixel library's setBrightness() function applies a rather elegant gamma correction), but you need to handle the issue one LED at a time.
Please be positive and constructive with your questions and comments.