I am working on a design and thought I’d share the journey.
It is for a backlighting for a wall trim. I have the following about 4ft above the floor hanging horizontally (link)
I can send more picture of the metal structure, diffuser, LED channels, etc.
The backlighting would be from the top and the bottom of the trim.
This is a view of the U channels I use in the back of the trim to fit the LEDs.
I am also using a diffuser like this one.
I did not want the leakage from the WS2815 LEDs to be an issue as they will be always connected, so the power for them would be switched, but wanted the ESP32 to be powered.
Came up with the following design:
The intent is to have 2 independents channels for two strips. And the power for the strip would be switched using the relays.
You can chose to only have a single relay for both strips, or a single strip, but the design is configurable to suit your need. I am using it for both given the amount of LEDs. The current limitation is based on the relays.
The whole design is powered by an external 12V AC-DC controller.
I added a 12V ADC monitor in case I want to use the ADC to measure any drops in my 12V line as I will have a few of these daisy chained on the 12V rail, so I can inject another supply along the way if necessary.
The design should accommodate WLED or ESPHome with some pros and cons.
WLED:
Pro: Easiest way to control an LED strip that I have found, with great effects, support, etc.
Cons: Cannot control 2 independent relays for each channel.
Workaround: I added a jumper between the GPIO for relay 1 and relay 2, so you can still control 2 independent 10A channels with a single relay output from ESP32.
Will not support the ADC function for the 12V monitoring. Again manageable with a multimeter for debugging during installation.
ESPHome:
Pro: Full flexibility of your program
Con: Well, you’ll have to do the coding for everything you want.
I wanted the board to be low profile, and as small as possible. I am attempting to fit into 3.94 x 2.36 x 0.98 inch box
Didn’t want to reinvent the wheel, so I embedded an off the shelf 5V regulator
Wanted the relays to be placed on top of my PCB and the pins sticking out from the bottom of the relay module board to be soldered to my board. Reduces the cabling inside the box.
This is the PCB design:
Top:
Bottom:
3D views:
Disclaimer: The 3D models I got are not yet verified to be the perfect matches for my hardware. I will be back home next Friday and will print and size to match all hardware vs. designed PCB before I order the PCB. (you can see a slight offset on the mounting holes for the relay boards, and you will see it also in the next view for the 5V regulator board.
All these will be fixed when I am back at home in front of the hardware vs. designing while traveling, so stay tuned.
Welcome any inputs, corrections, improvements, etc. and more importantly any gotchas. Will incorporate before I finalize. I will be sharing my design if anyone is interested. I use Diptrace for my design capture.