I would like to be able to control 600 LEDs individually, set up in a matrix. I would prefer to have each RGB LED have the option of controlling the brightness through PWM if feasible. I am just not sure on how I should approach this project. After searching around, I found a component that might be able to help me:
Would this method work with transistors for each RGB bulb? Is there another method I can use that would be more efficient, less expensive, or easier?
Thanks
Do you mean 600 RGB LEDs (1800 LEDs) or 200 RGB LEDs (600 LEDs)? You will probably have to use smart LEDs like the NeoPixel.
johnwasser:
Do you mean 600 RGB LEDs (1800 LEDs) or 200 RGB LEDs (600 LEDs)? You will probably have to use smart LEDs like the NeoPixel.
I am referring to 600 physical LEDs.
An RGB led as 3 physical leds in it, so your answer doesn't really help answer the question!
I agree with John. Use ws2812B leds or similar. Far simpler and cheaper than using other driver chips.
If you need 600 RGB leds, an UNO or similar like Nano will be able to run them, but it will require almost the entire available RAM. A Pro Micro has a little more, so that might be an option.
Paul
PaulRB:
An RGB led as 3 physical leds in it, so your answer doesn't really help answer the question!I agree with John. Use ws2812B leds or similar. Far simpler and cheaper than using other driver chips.
If you need 600 RGB leds, an UNO or similar like Nano will be able to run them, but it will require almost the entire available RAM. A Pro Micro has a little more, so that might be an option.
Paul
I see what you mean by the physical LEDS in the RGB, sorry. Therefore I meant 200 LEDs.. Also, how would I go about wiring an UNO to power so many LEDs?
Arduino does not power the LEDs. It just controls the data pins.
The Adafruit website has a lot of info.
https://learn.adafruit.com/category/leds
Google "digital LED strip".
AFAIK there are strips with three separate coloured LEDs (12volt strips), and strips with three colours inside one LED (5volt strips). Only the last type can mix colours and make white.
Leo..
Wawa:
Arduino does not power the LEDs. It just controls the data pins.
The Adafruit website has a lot of info.
Adafruit Learning System
Leo..
I know, I have a designated power supply for the LEDs. I am just wondering how I can wire the Arduino to trigger the LEDs. Do I need to use transistors?
PaulRB:
I agree with John. Use ws2812B leds or similar. Far simpler and cheaper than using other driver chips.
I agree with "simpler" but not "cheaper".
I think there are lots of less expensive ways to have a bunch of RGB LEDs than to use WS2812B or the like.
Here's an example of using shift registers to control a bunch of RGB LEDs. I'm almost sure the shift register approach is less expensive than the individually addressable LEDs.
As the video showed, it's tough to control the individual brightness level of each LED beyond 5-bits using shift registers but an advantage shift registers have over WS2812B LEDs is the brightness of the entire array can be controlled by using PWM on the shift register's enable pin. So the shift register controlled LED would have better color depth at low brightness levels.
The lack of brightness control (while maintaining color depth) of the individually addressable LEDs is probably my biggest complaint against them (though I still think they're very cool).
@Johngianni, what sort of LEDs did you want to use? How big? How bright? You mentioned wanting to use them in a matrix, how much space between each LED do you want? Have you seen the individually addressable Christmas lights? These are also pretty cool.
Johngianni:
I know, I have a designated power supply for the LEDs. I am just wondering how I can wire the Arduino to trigger the LEDs. Do I need to use transistors?
This all depends on the specific LED you plan to use.
Wawa:
Arduino does not power the LEDs. It just controls the data pins.
The Adafruit website has a lot of info.
Adafruit Learning SystemGoogle "digital LED strip".
AFAIK there are strips with three separate coloured LEDs (12volt strips), and strips with three colours inside one LED (5volt strips). Only the last type can mix colours and make white.
Leo..
I am aware of the LED strips but the project I am working would not work with an LED strip as the holes in the LEDs are placed is spaced out differently from the LED strip and cutting the strip in to segments would not fix the issue.
The LEDS I would use would have to be something I could buy in bulk in order to minimize the cost.
http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20151215161709&SearchText=rgb+led+diode
I would need to use lights lights like these in which they will be placed in all the holes of the platform. I assume that they would have to be common anode.. I am not looking for lights that are extremely bright but I am also not looking for ones that are too cheap. The project that I am doing involves a workbench in which I want to put LEDs throughout the entire pegboard. Therefore, an LED would be in each individual hole of the pegboard.
Is there a big difference between these two?:
or
Johngianni:
I would like to be able to control 600 LEDs individually....
The LEDs you linked to are just bare LEDs.
How are you going to control/PWM them.
Leo..
Look for these in bulk somewhere:
or
Wire power, Gnd to each device, then data out to data in across all 200.
or
https://www.sparkfun.com/products/11020 20 prewired, if you want to save time/effort
Control with neopixel library.
Adafruit.com also has strands of 25 LEDs like the above, search rgb led, scroll down thru the results.
Wawa:
The LEDs you linked to are just bare LEDs.
How are you going to control/PWM them.
Leo..
Sorry, I am still new to many things.. Would it make sense to then go for WS2812B LEDs?
CrossRoads:
Look for these in bulk somewhere:
https://www.sparkfun.com/products/12986
or
LED - RGB Addressable, PTH, 5mm Clear (5 Pack) - COM-12999 - SparkFun ElectronicsWire power, Gnd to each device, then data out to data in across all 200.
or
https://www.sparkfun.com/products/11020 20 prewired, if you want to save time/effortControl with neopixel library.
Adafruit.com also has strands of 25 LEDs like the above, search rgb led, scroll down thru the results.
Wow, these seems really easy to use.. Also, what is the difference between the WS2812S and WS2812B?
Yes, otherwise you need 600 PWM controllers.
Can do it with 34 of these - or just get the LED with the controller built in.
Maybe back up a step:
"I would prefer to have each RGB LED have the option"
So did you want to control the color/brightness individually? Or just the brightness of Red, of Blue, and of Green?
The former needs individual LED control, the latter you could get away with just 3 PWM controls, one per color, but 600 current limit resistors.
WS2812S vs B - need to read the datasheets to find out.
WS2803-preliminary-En.pdf (437 KB)
CrossRoads:
Yes, otherwise you need 600 PWM controllers.
Can do it with 34 of these - or just get the LED with the controller built in.Maybe back up a step:
"I would prefer to have each RGB LED have the option"
So did you want to control the color/brightness individually? Or just the brightness of Red, of Blue, and of Green?
The former needs individual LED control, the latter you could get away with just 3 PWM controls, one per color, but 600 current limit resistors.WS2812S vs B - need to read the datasheets to find out.
I would like to control the color/brightness individually but if it is not too difficult..
"This is the older 'S revision of the WS2812 LED chips with 6 pins, not 4! It is code compatible and the same over-all shape and functionality but not the same pinout so you cannot use these to replace an 'B chip. If you are designing a new PCB we suggest going with the B, since it has built in polarity protection. Other than that, B and S are the same brightness, and use the exact same code interface. "
Has seperate power pins for the controller and for the LEDs, and one unconnected pin.
Individually: then WS2812B, in prewired strips if you want to save time, and wired yourself if you have time to kill.
CrossRoads:
"I would prefer to have each RGB LED have the option"
So did you want to control the color/brightness individually? Or just the brightness of Red, of Blue, and of Green?
I would like to be able to control the color/brightness individually if it is not too difficult..
The WS2812 LEDs can be controlled individually, colour and brightness both.