WS2812B cable runs

There are two types of cable required for this and part of this depends on how your going to wire up the leds and how many in a strip

each LED will consume about 60mA at 5V (3 leds per chip at 20mA each running from 5V supply) so 100LEDS will consume about 6 Amps if full on white, thats a lot of current to go down a single wire and you will find that the LEDS at the end will be dimmer that those at the beginning as there will be a voltage drop along the power wires so you need to break up the power distribution into smaller sets of say 30 LEDs.

You can still run the data line from a single pin of the controller as each LED will buffer the data to the next LED and you can chain upto about 1000 LEDs and still get a refresh in excess of 50 times per second

you do not need resistors for these as they have constant current regulators built in but it is essential that you put in the decoupling capacitors for at least every other LED if there close together or every LED if further apart. If your buying the Strips already made up then this is already done for you, just run seperate power to each strip, and daisy chain the data if you want it all from a single pin

Hope this helps

There are two types of cable required for this and part of this depends on how your going to wire up the leds and how many in a strip

each LED will consume about 60mA at 5V (3 leds per chip at 20mA each running from 5V supply) so 100LEDS will consume about 6 Amps if full on white, thats a lot of current to go down a single wire and you will find that the LEDS at the end will be dimmer that those at the beginning as there will be a voltage drop along the power wires so you need to break up the power distribution into smaller sets of say 30 LEDs.

You can still run the data line from a single pin of the controller as each LED will buffer the data to the next LED and you can chain upto about 1000 LEDs and still get a refresh in excess of 50 times per second

you do not need resistors for these as they have constant current regulators built in but it is essential that you put in the decoupling capacitors for at least every other LED if there close together or every LED if further apart. If your buying the Strips already made up then this is already done for you, just run seperate power to each strip, and daisy chain the data if you want it all from a single pin

Hope this helps

Thank you for your replies.

To be a little more specific:

• There will be 85 WS2812B LEDs
• Each single WS2812B LED will be separated by 500 mm of cable (yes - I am cutting them up).

So for powering them, I could run 5V:

1. to each individual one without using the pass-through on the LED module
2. just wire them normally using the pass-through
3. a combination (as suggested by P.Oakes)

The WS2812B chips I am looking at don't appear to have power pass-through connections. Do you have a make/model of the units you are thinking of using?

Peter Oakes wrote:

 

each LED will consume about 60mA at 5V (3 leds per chip at 20mA each running from 5V supply) so 100LEDS will consume about 6 Amps if full on white, thats a lot of current to go down a single wire and you will find that the LEDS at the end will be dimmer that those at the beginning as there will be a voltage drop along the power wires so you need to break up the power distribution into smaller sets of say 30 LEDs.

 

Good point