#Ultra-thin# 1.9-inch segment electronic thermometer and hygrometer

Project Overview:

This project aims to design and develop an ultra-thin 1.9-inch segment e-ink display for thermometers and hygrometers, utilizing a low-power 1.9-inch segment e-ink screen. The core controller is the ESP8685, featuring 2.4 GHz Wi-Fi and BLE 5 functionality. To ensure high data accuracy and reliability, a high-precision Swiss sensor was selected. The device has a built-in battery and is equipped with a magnet for easy attachment to refrigerator surfaces, facilitating everyday household use.
Project Background:
Modern households have increasingly higher demands for environmental monitoring equipment, especially in temperature and humidity monitoring. While existing thermometers and hygrometers on the market are feature-rich, most are bulky and aesthetically unappealing, and the accuracy and power consumption of some products need improvement. Therefore, developing an ultra-thin, low-power, and high-precision thermometer and hygrometer is of significant importance.
Key Components:

1.9-inch segment e-ink display
controller, ESP8685
high-precision Swiss sensor,
built-in battery and magnets.

Hardware Design: The circuit board
uses a four-layer PCB design (JLC04101H-3313, 1mm thickness)
with low power consumption (standby <8μA).
Components include
a 300nA low quiescent current LDO.
Built-in battery :
252030 3.7V@110mAh high-capacity battery .
Built-in magnets:
Three strong magnets allow easy adhesion to surfaces such as iron, nickel, and cobalt . Software Design:

Sensor Data Reading:
Data is read from the Swiss sensor via an I2C interface, periodically collecting environmental temperature and humidity values.
Displayed on the segment e-ink display. The interface is simple and clear, facilitating quick data retrieval.
Power Consumption Control:
Reduces CPU operating frequency.
In idle state, it enters low-power sleep mode.
To save power, data is collected every ten minutes.
Battery Warning:
When the battery voltage is below 3.4V, the thermometer and hygrometer display a low battery icon.
Firmware Burning:




Wireless Communication

: Temperature and humidity data can be uploaded to a cloud server via Wi-Fi for remote monitoring. It also supports BLE communication, allowing users to read device data via a mobile app and perform operations such as parameter settings. (Real-world scene footage)