Gravity: GNSS GPS BeiDou Positioning Module with RTC - I2C&UART

The Gravity GNSS GPS BeiDou Positioning Module with RTC combines high-precision satellite positioning with an onboard real-time clock. It is designed for students, makers, and engineers developing low-power environmental loggers, astronomical timers, and NTP time-servers. Supporting both I2C and UART communication, the board integrates seamlessly with Arduino, ESP32, and Raspberry Pi.

Automatic satellite clock calibration

The module periodically acquires satellite time to calibrate its onboard SD3031 RTC chip automatically. This eliminates long-term time drift and accidental timing errors, maintaining RTC accuracy of plus or minus 3.8ppm at 25 degrees Celsius.

Energy-efficient power management

To minimise battery drain, the module automatically powers down the L76K GNSS chip after calibration, dropping power consumption to under 1mA with only the RTC active. Users can also configure the GNSS to stay continuously enabled at 46mA when persistent tracking is required.

Microcontroller wiring and connectivity

Featuring both I2C and UART interfaces, the board operates across a 3.3V to 5V DC supply range. It hooks up directly to mainstream microcontrollers such as the DFRduino UNO R3, ESP32, or Raspberry Pi using standard Gravity cables.

Positioning accuracy and telemetry output

The integrated L76K GNSS receiver achieves a 2.0m CEP positioning accuracy with a 30-second cold start and 2-second hot start. It outputs detailed longitude, latitude, altitude, and real-time timing data.

Compact board and package contents

Measuring 32mm by 42mm, the module includes an external GPS/BeiDou active ceramic antenna with an IPEX1 connector, a Gravity 4-pin sensor cable, and a 10-pin connector header.

Downloads & documentation

• Product wiki (DFRobot)