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.

lucky-resistor-1

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.

lucky-resistor-2

I mounted everything on a very small breadboard and did all connections to the Arduino.

lucky-resistor-3

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.

And the Winner is…

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.

The List of Tested LEDs

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

Video

Just for fun, here a video where I used the test setup to create an animated chain of lights.

Thank you!

If you have any questions, please leave a comment below.

Have fun!