More info please click here:http://img.banggood.com/file/products/20160328211703MINI,D1,%E8%B5%84%E6%96%992.pdf
Here is the schematic diagram:http://img.banggood.com/file/products/20160328211732%E5%8E%9F%E7%90%86%E5%9B%BE.pdf

Description:

The D1 mini is a mini wifi board based on ESP-8266EX.11 digital input/output pins, all pins have interrupt/pwm/I2C/one-wire supported(except D0)
1 analog input (3.3V max input)
A Micro USB connectionCompatible with: https://github.com/esp8266/Arduino
Compatible with: http://www.nodemcu.com/index_cn.html
Package included:

1 x D1 Mini
2 x Lange Weibliche Pins2 x Kurze Weibliche Pins2 x Normal Pins