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By radioboy86
#198783
Hello my name is Jonathan and I have a question for anyone here that is all the wiser than me.




I need help on powering X5 LEDS from an AC-DC power adapter. The IR LEDS are rated for 940nm and are 1.2-1.5V and they each use 20-30ma current amps.

Would a 6V AC-DC power adapter with 100ma work and be safe? I do not want to add resistors. I am trying to get the LEDS to match the voltage and current based on the total amount of LEDS I am using which is X5. IR LEDS 940nm type. Here is the link. Do you sell one like this I can buy in bulk?

https://www.amazon.com/gp/product/B01BV ... UTF8&psc=1



IR LED - 940nm Infared LED Diodes
(1.2V - 1.5V) Rated voltage

1.2v X 5 IR LEDS = 6V TOTAL
1.5v X 4 IR LEDS = 6V TOTAL

(20-25ma)

20 X 5 IN SERIES = 100ma TOTAL ALL LEDS / PERFECT MATCH TO AC-DC
25 X 4 IN SERIES = 100ma TOTAL ALL LEDS / PERFECT MATCG TO AC-DC
30 X 5 IN SERIES = 150ma OVERCURRENT OF 50ma, 50ma more amps than 100ma
30 X 4 IN SERIES = 120ma OVERCURRENT OF 20ma, 20ma more amps than 100ma


I assume I could use either X4 IRLEDS total or X5 IR LEDS total correct? That would be safe on a 6V 100ma AC-DC Power adapter?
I do NOT want to add a resistor, I am trying to get the amps and volts to safe levels without adding the heat consumption of a resistor too.