INTRODUCTION

The Gravity GNSS Positioning & Timing Module integrates satellite positioning functionality and a real-time clock (RTC). The module automatically obtains satellite time based on a preset calibration period and accurately calibrates the onboard RTC chip. This calibration effectively eliminates time errors caused by the RTC chip during extended operation or accidental situations.

The system automatically cuts off power to the GNSS chip after calibration, significantly reducing overall system power consumption compared to GNSS-only solutions. Additionally, the user has the option to use the module as a positioning module by setting GNSS active all the time， providing accurate longitude, latitude, time, altitude, and other data.

The module offers two data output types: I2C and UART. It is compatible with Arduino, ESP32, Raspberry Pi and other mainstream control devices. Ideal for scenarios requiring extended working hours and high-precision time, such as astronomical observation timers, NTP servers, and outdoor wireless sensor time synchronization.

The differences between Gravity: GNSS Module with RTC Function and Gravity: GNSS Receiver Module:

Unlike the traditional Gravity: GNSS GPS BeiDou Receiver Module - I2C&UART, which is a single GNSS module with high power consumption and is only suitable for outdoor scenarios, this Gravity: GNSS Module with RTC Function offers a significant improvement.

The Gravity: GNSS GPS BeiDou Positioning Module with RTC Function has the ability to turn off the GNSS when not in use, leaving only the RTC module to maintain time, resulting in lower power consumption.

Figure: Wiring Diagram of Gravity: GNSS Positioning Timing Module and DFRduino UNO R3

Figure: Positioning &Timing Results Display

FEATURES

Integrated GNSS and RTC Functionality

Automatic Satellite Time Calibration

RTC Chip Calibration

Power Efficiency

Satellite Signal Loss Mitigation

SPECIFICATION

Operating Voltage: 3.3~5V DC

Output Signal: I2C/UART

GNSS IC: L76K

GNSS Accuracy: 2.0m CEP

First positioning time: 30s (Cold start), 2s (Hot Start)

Operation current:
       GNSS enable: 46mA
       GNSS chip off ＜1mA

Antenna Interface: IPEX 1

Antenna Frequency: 1561~1575.42MHz±3MHz

RTC IC: SD3031

Time range: Year 2000~2099

Time Accuracy: ±3.8ppm @25℃

PCB Size: 32mm*42mm

DOCUMENTS

Product wiki

Schematic

Dimension & Layout

SHIPPING LIST

Gravity: GNSS Positioning & Timing module x1

GPS / BeiDou Active Ceramic Antenna (IPEX1 Connector) x1

Gravity 4P sensor cable x1

10 P connector x1