First of all: this the first time I used an Adafruit product and while it costs more comporaed to other sites I am glad I did purchase it there for the followin reasons:
- It works
- It a very good quality and the design is good
- all is open source/visible source
- go look for yourself: https://learn.adafruit.com/adafruit-feather-huzzah-esp8266/downloads
At the downlaod page everything is linked, the shamatics the PCB files and also th datasheets of the components.
I did dig around the the ESP8266 itself only draws ~20µA while in deepSLeep but as there are also other components on the board the current piles up. The 3.3V regulator has an EN pin to disable it.
Powering the board via 3.3V with 3.3V regulator enabled: 6.8mA
without 3.3V regulator: 9.5mA without resistor and with 100k resistor 6.7mA, but then it seemed like the regulator was still working.
Without damaging the board there is not realy a way to disable the USB-Serial converter nor the LiPo charger, without them maybe we could get low enough.