To achieve this he created Fade, a custom programming language/framework for controlling LED animations from the ESP32. Fade is written for addressable RGB LEDs like the Neopixel/WS2812.

As the main cap voltage falls the led current falls – to the point where there is not enough Vbe to keep the pnp on, which starves the base of the npn – so the whole circuit snaps off again. With the ...

Of course, the resistor also has to have a sufficient view of the LED. You might use this as a safety light that only works in the dark. A simple circuit, but it just goes to show that we tend to ...