Leds in parallel

Thread Starter

joseimaz1

Joined May 13, 2014
2

Papabravo

Joined Feb 24, 2006
12,506
You can adjust the required current to any value over a range. For example you could use 5 ma per LED or 15 ma per LED. the choice makes a huge difference in the required current. The problem is actually in the current carrying capacity of the cable, not the power supply. If you daisy chain the 5V you will experience IR drop on the 5V line and a similar drop on the ground return. If you split the power cables from the data cables so that there is a low impedance path to the supply and ground return you should be set to go.

512 * .005 = 2.56 A which is a great deal less than your calculations.
 

Thread Starter

joseimaz1

Joined May 13, 2014
2
You can adjust the required current to any value over a range. For example you could use 5 ma per LED or 15 ma per LED. the choice makes a huge difference in the required current. The problem is actually in the current carrying capacity of the cable, not the power supply. If you daisy chain the 5V you will experience IR drop on the 5V line and a similar drop on the ground return. If you split the power cables from the data cables so that there is a low impedance path to the supply and ground return you should be set to go.

512 * .005 = 2.56 A which is a great deal less than your calculations.
Ok, thanks for your response. Assuming use 30mA per LED. What is the maximum number of LEDs in parallel from a single source output you recommend?

regards
 

Papabravo

Joined Feb 24, 2006
12,506
Ok, thanks for your response. Assuming use 30mA per LED. What is the maximum number of LEDs in parallel from a single source output you recommend?

regards
Remember that each PIXEL consists of 1 RED, 1 GREEN, and 1 BLUE LED. That means each PIXEL could consume 3*30 mA 90 mA

512 * 90 mA = 46.08 A

You cannot send 46 A down a 2mm cable. You have to take the +5V and GND cables out of the daisy chain and run separate wires back to the power supply.
 
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