3.3V USB Converter/Adapter

thingiverse

Here's the lowdown: Get your hands on a USB-A male to USB-A female converter/adapter with an integrated 3.3V voltage regulator AMS1117-3.3. It comes in handy for programming and powering a device like an Arduino when you only want to run it with 3.3V instead of the standard 5V, especially if you've got 3.3V components on board (ESP8266, NRF24L01, etc.). This little gadget also does a number one for converting a 5V logic level USB-RS232 converter into a 3.3V one (like for ESP8266). Just slap it onto your Arduino and run with it at 3.3V - no need for pesky level shifters getting in the way. Parts used: http://www.aliexpress.com/item/-/32351569056.html (AMS1117-3.3) http://www.aliexpress.com/item/-/1924302835.html (USB male) http://www.aliexpress.com/item/-/1228315433.html (USB female) http://www.aliexpress.com/item/-/1554364460.html (10µF caps, optional, depending on the job)