XIAO Logger HAT

The XIAO Logger is a small add-on HAT designed for XIAO and QT Py boards that improve their data logging capabilities. It has a Sensirion SHT40 sensor for precise temperature and humidity measurements, a BH1750 sensor for ambient light detection, and a PCF8563 real-time clock to maintain accurate timekeeping. When connected with the lithium-ion battery, there is a voltage divider to monitor battery levels, making sure your projects can track environmental data and power status effectively. This HAT is ideal for projects requiring environmental monitoring and data logging, such as weather stations, smart gardening systems, or portable data loggers. Note: Li-ion battery NOT included Features

* Tiny footprint: Fits neatly on all Seeed Studio XIAO microcontroller boards. With a small lithium-ion battery sandwiched between the dev board and its hat, the logger is well-fitting for space-limited projects.

* Power supply enable: The GPIO-powered sensors allow almost a no-power sleep mode when the sensors are not used. The always-on RTC consumes less than 1 uA making it suitable for battery-powered data loggers.

* I2C communication: Easy to program from existing libraries and supports adding more sensors on the same bus.

* On-board RTC: The PCF8563 chip with its oscillator provides timekeeping, essential for long-term data loggers, and a programmable interrupt for deep sleep wakeups.

* Accurate Monitoring: The SHT40 temperature sensor presents temperature readings with 0.2°C accuracy and humidity with 1.8%RH. The PCF8563 real-time clock has shown a 7-minute time shift over one year compared to 10 hours from the ESP32’s internal RTC.

* Battery Voltage Monitoring: When connected with the lithium-ion battery, its status level can be safely monitored through a pin-enabled voltage divider.

* Product Number: Seeed 114993446

What's on Board

Specifications

Size 21 x 17.8 mm

Operating Temperature -40°C to 85°C

Power Supply Range 2.4V ~ 3.6V

Current consumption ~ 500uA

Idle current consumption ~ 0.25uA

Communication Interface I2C

SHT40 Temperature & Humidity Sensor

BH1750 Ambient Light Sensor

PCF8563 Real-Time Clock

ADC

Battery Voltage Read

SHT40 temperature & humidity sensor read time ~ 2ms

BH1750 ambient light sensor read time ~ 120ms

Compatible Hardware Platforms Seeed Studio XIAO

Battery EEMB 3.7V Lithium Polymer Battery (500mAh)

Resources

* XIAO Logger Hat schematics

* XIAO Logger Hat layout

* XIAO Logger Hat gerber

* SHT40 temperature & humidity sensor datasheet

* BH1750 ambient light sensor datasheet

* PCF8563 datasheet

* XIAO Logger Hat project GitHub

Package Contents

* 1x XIAO Logger Hat Board

* 1x 7-pin Female Header