published: February 16, 2017 — last modified: October 23, 2025
Today I tested a number of SMD LEDs for the plant watering sensor project. I soldered all 13 LEDs I shortlisted onto a small board and connected it to an Arduino Zero Pro. So I could try the different flashing styles I planed to use more or less automatically. That way I could focus on the LED flashing itself, without being distracted by switching cables.
This is the board I made. Very simple but functional. I used red and blue male header to mark the anode and cathode of the LEDs. There is a sticker on the bottom with the LED numbers on it.
I mounted everything on a very small breadboard and did all connections to the Arduino.
You can clearly see the difference between the LEDs. With the eyes, the difference is even more visible. It is very interesting how much light all these LEDs produce from more or less the same 20mA. To be fair, because of the different voltages, not all LEDs got the same current - the test was very specific for my intended use with a 3V coin cell.
Absolutely the LEDs from Sloan. Especially the green LED with the product number SMD-G0805-02 is impressive - the colour and brightness is almost surreal. I had to double check this LED really only draws 20mA for this incredible brightness. A short 40ms flash from this LED is even at normal daylight very good visible.
You can see from on the photo from left (1) to right (13).
| Nr | Colour | mcd | mA | Vf | Article Number |
|---|---|---|---|---|---|
| 1 | Mega Green | 200 | 20 | 2.1 | Kingbright KP-3216SEC |
| 2 | Brilliant Green | 405 | 20 | 3.3 | Everlight 17-21/GHC-XS1T2M/3T |
| 3 | Super Bright Green | 12 | 20 | 2.2 | Kingbright KP-3216SGC |
| 4 | Green | 520 | 20 | 3.2 | Sloan SMD-G0805-02 |
| 5 | Brilliant Yellow Green | 90 | 20 | 2.0 | Everlight 17-21/G6C-AP1Q1B/3T |
| 6 | Super Bright Yellow | 80 | 20 | 2.0 | Kingbright KP-3216SYC |
| 7 | Yellow | 140 | 20 | 2.0 | Sloan SMD-Y0805-02 |
| 8 | Super Bright Orange | 200 | 20 | 2.0 | Kingbright KP-3216SEC |
| 9 | Hyper Red | 230 | 20 | 1.95 | Kingbright KP-3216SURC |
| 10 | Super Bright Red | 100 | 20 | 1.85 | Kingbright KP-3216SRC-PRV |
| 11 | Red | 100 | 20 | 1.9 | Sloan SMD-R0805-02 |
Just for fun, here a video where I used the test setup to create an animated chain of lights.
[youtube https://www.youtube.com/watch?v=hJPSCPqA2Kk&w=560&h=315]
If you have any questions, please leave a comment below.
Have fun!
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