Requirements:
- Diffused RGBW light that is great for reading that can be mounted to the wall
- Requires different modes of operation. a) Crazy light show b) Adjustable R G B and W light via faders
- Reading mode should start out at the set brightness and then fade incrementally for an hour until eventually shutting off. You shouldn’t notice the light is getting dimmer.
This was a basic project. The ESP32 is overkill for this, but I had it on hand. For linear faders that are normally used on a mixing console create voltage dividers that are read by the ADC on the ESP32. The light is dimmed with standard PWM and MOSFETs. Fun artifact. My son wanted to know why his ceiling fan was spinning backwards. He learned all about aliasing! Fun stuff. The PWM frequency I chose is just a hair faster than the rotation of the fan. Persistence of vision says humans can see light when it blinks fast enough, but tell that to the fan. It knows!
Lessons Learned
I don’t know what I was thinking! I used a linear regulator to step down from 12V to 3.3V. That’ll never happen again. Dissipating 8V+ when an ESP32 is pulling hefty power for a modern microcontroller is a bad, bad idea. I should have used a switching regulator. People worry about the noise. Fair enough. I worry about melting!
Those hefty VM3.96mm connectors at ref des: J5 and J3 are strong. They are also a bit too snug. They are meant to be plugged in and stayed plugged in. That’s good. The problem is if you ever want to take the connector off. They are kinda terrible. Granted, I’m sure I got these from Ali Express for $0.00001. Maybe you get what you pay for sometimes.
This was a fun little project. The greatest challenge was getting the clearance right on the 3D printed “tracks” for the LEDs.
As always I always struggle with wiring and connectors. The NAME OF CONNECTOR GOES HER wasn’t nearly as handy for plugging and unplugging as I had hoped. I used an RJ45 connector for the ESP32 to talk to the fader. That worked well. The lesson is a consumer-approved connector should always be used for “consumer approved tasks” whatever that means.
