Rotary Encoder - Illuminated (RGB) Datasheet Questoions

Components & Accessories LEDs
1

After looking through the datasheet for the [RGB encoder, I have some follow up questions. Email support suggested I should make a post here to get help. (Questions are numbered for ease of response)

For the LED’s included in the encoder, the datasheet says they have a forward voltage of 5V.

  1. Is this value correct? It seems high for a standard (i.e. non high-power) LED.

  2. No value is given for the forward current, does Sparkfun know what this value is?

  3. Is the forward voltage the same for each led?

  4. Assuming the forward voltage is in fact 5V, is my assumption correct that when powered at 5V, these would not require a series current limiting resistor?

Thank you in advance](Rotary Encoder - Illuminated (RGB) - COM-15141 - SparkFun Electronics)

2

All of the info made available by the manufacturer is here https://cdn.sparkfun.com/assets/4/e/e/b … _RGB.pdf

The example (under the documents tab) makes mention of:

/ Note that because this is a common anode device,

// the pushbutton requires an external 1K-10K pullDOWN resistor

// to operate.

Here https://github.com/sparkfun/Rotary_Enco … ncoder.ino

3

Hi TS-Russell,

Thanks for taking the time to respond.

TS-Russell:
All of the info made available by the manufacturer is here https://cdn.sparkfun.com/assets/4/e/e/b … _RGB.pdf

Yes, that is the datasheet I was referring too, and I have made this post precisely because information would appear to be missing from the datasheet. However, it appears Sparkfun have used the same component in other designs, such as QuickTwist, and the values I am requesting would have been used in that design.

TS-Russell:
The example (under the documents tab) makes mention of:

/ Note that because this is a common anode device,

// the pushbutton requires an external 1K-10K pullDOWN resistor

// to operate.

Here https://github.com/sparkfun/Rotary_Enco … ncoder.ino

That has to do with the button, however I am asking about LED’s.

If anyone from Sparkfun could comment that would be appreciated.

Thanks

4

The schematic for the qwiic twist can be found at https://cdn.sparkfun.com/assets/1/8/1/7 … ematic.pdf (see the Documents tab on most Sparkfun pages for the schematics)

They are using 10 ohm resistors driven by an ATTiny84 running on 3.3v, however that is using a Bourns encoder. The data sheet for it is at https://cdn.sparkfun.com/assets/5/e/e/9/b/PEL12T.pdf and specs the LEDs.

/mike