This is ESP8266 (ESP-12F) and HX711 based weight monitoring device.

• Designed to be pretty small.
• Supports multiple load cells.
• Can be populated with 18650 battery
• Can be operated in ultra low power mode

Dev NOTE: before commit, run ./kibot.sh to regenerate documentation, bom, gerbers and other assets.

• schematics.pdf
• pcb.pdf with dimensions
• ibom.html
• gerbers.zip

Normal operation

The circuit should be powered either via a USB connector on the LiPo charger or battery.

Assembly and hardware configuration notes

LiPo charger

Chargers(U301) with protection can be used.

For use without onboard charger R303 must be shorted and U301,R301 and R302 can be omitted.

Low-power sleep

A timer is equipped with selectable(SW301) wake-up settings(R304 and R305).

For applications that do not require a low-power sleep, timer can be bypassed by shorting out R306. Following components can be omitted in assembly:

• U302
• Q302
• SW301,SW302
• R304,R305,R307,R308

ADC configuration

To reduce noise on measurements capacitors(C401,C402,C403) on ADC input are placed. As a side effect, they slow down reading settling time after weight change. Removing these capacitors will give a fast reading but increase spread by about 3 times.