In r0.1 we used a addressable LED for the RGB LED, this doesn't make immediate sense because its a single LED, but this needs only one line to drive, and in the end its more compact (if we wanted to take advantage of 5v for a regular led)
I'm considering going with a regular LED, but there's not enough space for a regular led using the 5v, because the ios are not 5v tolerant and would require 3 transistors, alternative solution is a 74LVC3G17 (3 gate schmitt trigger) as a level shifter, or we could go with direct drive. The reason 5v drives is prefereable to direct drive is that blue and green leds usually have high forward voltages (3.2 - 3.4V), and driving them with 3.3V will result in a weak color range (harder to achieve white for instance)
one other reason to consider keeping the addressable led is the ability to add extra leds by the user (we need to add a easier way to connect to it though, like some edge pads)
In r0.1 we used a addressable LED for the RGB LED, this doesn't make immediate sense because its a single LED, but this needs only one line to drive, and in the end its more compact (if we wanted to take advantage of 5v for a regular led)
I'm considering going with a regular LED, but there's not enough space for a regular led using the 5v, because the ios are not 5v tolerant and would require 3 transistors, alternative solution is a 74LVC3G17 (3 gate schmitt trigger) as a level shifter, or we could go with direct drive. The reason 5v drives is prefereable to direct drive is that blue and green leds usually have high forward voltages (3.2 - 3.4V), and driving them with 3.3V will result in a weak color range (harder to achieve white for instance)
one other reason to consider keeping the addressable led is the ability to add extra leds by the user (we need to add a easier way to connect to it though, like some edge pads)