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Syed Arslan Ali Zaidi
Syed Arslan Ali Zaidi
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I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.

The more I am reading about power requirements of a matrix the more I am getting confused. As per my understanding, there will only be 1 LED lit at any given time (and it will remain lit for a delay of 300ms). Therefore, I need to calculate voltage and current limiting resistor according to just 1 LED. 1 resistor will be attached with each row. Some articles are suggesting that it needs to be calculated for 1 whole row...WHY? I cant digest the logic.

Please note that I do not intend to use any shift registers or current sink devices. Arduino alone. As also depicted in Arduino CookBook and certain other resources.

I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.

The more I am reading about power requirements of a matrix the more I am getting confused. As per my understanding, there will only be 1 LED lit at any given time (and it will remain lit for a delay of 300ms). Therefore, I need to calculate voltage and current limiting resistor according to just 1 LED. 1 resistor will be attached with each row. Some articles are suggesting that it needs to be calculated for 1 whole row...WHY? I cant digest the logic.

I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.

The more I am reading about power requirements of a matrix the more I am getting confused. As per my understanding, there will only be 1 LED lit at any given time (and it will remain lit for a delay of 300ms). Therefore, I need to calculate voltage and current limiting resistor according to just 1 LED. 1 resistor will be attached with each row. Some articles are suggesting that it needs to be calculated for 1 whole row...WHY? I cant digest the logic.

Please note that I do not intend to use any shift registers or current sink devices. Arduino alone. As also depicted in Arduino CookBook and certain other resources.

Source Link
Syed Arslan Ali Zaidi
Syed Arslan Ali Zaidi
  • 41
  • 1
  • 4

How to calculate power requirements of LED matrix, per row or per LED?

I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.

The more I am reading about power requirements of a matrix the more I am getting confused. As per my understanding, there will only be 1 LED lit at any given time (and it will remain lit for a delay of 300ms). Therefore, I need to calculate voltage and current limiting resistor according to just 1 LED. 1 resistor will be attached with each row. Some articles are suggesting that it needs to be calculated for 1 whole row...WHY? I cant digest the logic.