After I realized that 6 pins of the ESP-12F are literally unusable, changed the wiring a bit (I was able to keep most of the functionality with minor restrictions) tihs is fully routed and done. But I don't feel particularly good about the layout; I want to make it more compact.

This is an RGBW + WS2812 LED driver with ESP8266 and 3-A DC/DC regulator. There are headers for 3 PIR sensors, so it's possible to detect motion, and also in different sectors (movement direction on corridors).

The way this works is that if you use 12-V LED strips, you must provide 12-ish V at the input. There won't be any conversion, other than the board powering itself (5 V and 3.3 V)

To drive the LED strip, there are 4 MOSFETs, which are driven by an octal buffer (at 5 V) to reduce RDSon.

It's possible to drive WS2812-compatible digital LEDs, (ab)using the I2S output - thanks Charles Lohr. The signal is level shifted to 5 V.

Show thread

There is also a clock output provided, for the rare but excellent LED strips with synchronous data interface. All these data lines have Schottky diodes to 5 V and to GND, to protect against transients and hotplugging.

If these kind of 5-V powered LED strips are used, the on-board DC/DC can provide up to 3 A current, and the input can be anything between 5 V and 17 V. This makes cabling easier (less current - less copper needed.)

Show thread

From 12 V you can run conventional LED strips along digital ones simultaneously.

Show thread

This is the backside of the board. The carrier PCB is 55x30mm plus the antenna part of the wifi SoC module.

The DC jack is very large. And I also wish it would be on the opposite end of where the LED strip is, not orthogonal to it.

But then I'd need to make this board wider, and I wanted to keep it sleek, with possibility to solder the LED strip directly on it.

I want to keep this affordable as much as possible. A bunch of these modules could do very cool effects together.

Show thread

@uint8_t I really like the "⚠️ RTFM". When I get around to finally design a PCB, I'm totally stealing that!

· · Web · 1 · 0 · 1

@tbr it's good advice to read the fine manual

Sign in to participate in the conversation
Society of Trolls

A nice little Mastodon instance. Mild trolling encouraged (keep it local), but not required. Malicious behaviour is not tolerated. Follow Wheaton's law and you'll be fine.