3W LEDs, from Micro-controller, via MOSFETs
2020-Sep-06, Sunday 02:32 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
chebeTime to play with some super bright LEDs! (Just remember; do not look directly at them while powered.)
Kitronik have some lovely 3W LEDs (with unfortunate name) in a star shape for heat dissipation. They provide a datasheet with example circuit for 5V power source. It requires 2.2 ohm power resistors, which are new to me. But when I tried regular resistors there was a lot of smoke, so they are definitely required.
I want to control the lights from a lower voltage micro-controller, so I'm going to need some N-channel MOSFETs. This is my first time using these. The Data pin (from the Arduino) acts a switch to complete the higher power circuit that lights up the LED.
All together the circuit looks a bit like this.
First I solder leads onto the LEDs and the resistors, in a modular fashion.
Then I solder up the board. Using a ElectroCookie breadboard for cuteness. With 16 MOSFETs for individual control of 16 different 3W LEDs. And headers, many headers, for modularity.
Connect the resistors, LEDs, and Arduino, up to the MOSFET circuit board. Don't forget a common ground connection with the Arduino.
I'm using my 5V Voltage Regulator board. I'm also using a Trellis board (not NeoTrellis) to access many buttons over I2C. It's not strictly necessary, but it helps with testing without using too many pins, and the way the buttons light up in latching mode provides great feedback.
If you want one it's a bit of a project in and of itself, you'll need a Trellis PCB, 3mm LEDs, silicone button pad, and enclosure. (That enclosure is actually for the NeoTrellis, but if you leave off one of the walls it works just fine.)
I have the Trellis mapping one button to one LED. Pressing a button turns on the corresponding LED.
And then you can turn on others if you wish. The button pad tells you which ones you have on or off. (My project requires only one LED to be on at a time, so this was just for testing. You'll probably need a greater power supply if you want many on at once.)
Kitronik have some lovely 3W LEDs (with unfortunate name) in a star shape for heat dissipation. They provide a datasheet with example circuit for 5V power source. It requires 2.2 ohm power resistors, which are new to me. But when I tried regular resistors there was a lot of smoke, so they are definitely required.
I want to control the lights from a lower voltage micro-controller, so I'm going to need some N-channel MOSFETs. This is my first time using these. The Data pin (from the Arduino) acts a switch to complete the higher power circuit that lights up the LED.
All together the circuit looks a bit like this.
Fritzing diagram
Photo by chebe
First I solder leads onto the LEDs and the resistors, in a modular fashion.
3W star LED and power resistor, with leads soldered
Photo by chebe
Then I solder up the board. Using a ElectroCookie breadboard for cuteness. With 16 MOSFETs for individual control of 16 different 3W LEDs. And headers, many headers, for modularity.
16 MOSFET circuit soldered
Photo by chebe
Connect the resistors, LEDs, and Arduino, up to the MOSFET circuit board. Don't forget a common ground connection with the Arduino.
Hooking up MOSFET circuit board to 3W LEDs and Arduino
Photo by chebe
I'm using my 5V Voltage Regulator board. I'm also using a Trellis board (not NeoTrellis) to access many buttons over I2C. It's not strictly necessary, but it helps with testing without using too many pins, and the way the buttons light up in latching mode provides great feedback.
If you want one it's a bit of a project in and of itself, you'll need a Trellis PCB, 3mm LEDs, silicone button pad, and enclosure. (That enclosure is actually for the NeoTrellis, but if you leave off one of the walls it works just fine.)
Full arrangement, with buttons and power source, all off
Photo by chebe
I have the Trellis mapping one button to one LED. Pressing a button turns on the corresponding LED.
One 3W LED on
Photo by chebe
And then you can turn on others if you wish. The button pad tells you which ones you have on or off. (My project requires only one LED to be on at a time, so this was just for testing. You'll probably need a greater power supply if you want many on at once.)
Two 3W LEDs on
Photo by chebe
