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TinyDuino Processors & TinyShields / A question on a LED used in TinyCircuits
« on: October 13, 2016, 05:11:39 PM »
Hello TinyWorld 
Could somebody, please, explain me how LEDs in USB TinyShield (used for TX and RX indication, designated as D1 and D2 in the schematic) were chosen?
Namely, those are amber - which means that the voltage should be around 2 V. The resistor is of 1 kOhm and the supply voltage is 3.3 V. Now, the current through the LED in this case is:
I = (3.3 - 2) / 1000 = 1.3 mA
This seems like quite a low current for a LED... I looked through some LNJ packaged amber LEDs, and almost all of them require 10 mA... so, how does this actually work?
Thank you in advance.
drm
Could somebody, please, explain me how LEDs in USB TinyShield (used for TX and RX indication, designated as D1 and D2 in the schematic) were chosen?
Namely, those are amber - which means that the voltage should be around 2 V. The resistor is of 1 kOhm and the supply voltage is 3.3 V. Now, the current through the LED in this case is:
I = (3.3 - 2) / 1000 = 1.3 mA
This seems like quite a low current for a LED... I looked through some LNJ packaged amber LEDs, and almost all of them require 10 mA... so, how does this actually work?
Thank you in advance.
drm