With this design I want to add the following features:

  • Breadboard Compatibility

  • 3.3V Regulator

  • Inrush Current

I also considered adding an USB-UART Bridge but that would increase the size of the final board, which wasn't what I was aiming for. Perhaps in another time.

For the regulator I chose the SPX3819M5-L-3-3/TR because its cheap, small and easily available.

I also added 2 LEDs, one for power and the other for the pin D2 as a status pin. SMD LEDs don't need as much current as regular through hole LEDs. A simple 10K resistor is enough as opposed to maybe a 330 ohm resistor for through hole one.

Pull-up resistors were also added with the value of 10K.

On the 3.3V power line I added 4 47uF capacitors for a total of 188uF(theoretical) to fight the voltage drop with the initial inrush current of the esp8266.

Finally 2 momentary switches were added for the RST and BOOT