Hookup Guide
Schematic (GNSS Flex pHAT)Product Overview
Equip your Raspberry Pi with survey-grade, millimeter-level precision without sacrificing power or space with the SparkFun mosaic-G5 P3 GNSS Flex pHAT. This all-in-one Raspberry Pi peripheral combines our GNSS Flex pHAT with the SparkPNT mosaic-G5 P3 Module, featuring Septentrio's compact, energy-efficient receiver. This kit is the preeminent choice for surveying, robotics, and other IoT applications where size, weight, and power (SWaP) are critical constraints.
The GNSS Flex pHAT acts as the bridge between your Raspberry Pi and the modular SparkPNT ecosystem. It mounts securely via an extended 40-pin header and connects to the included GNSS module using standardized 2x10-pin headers.
- Raspberry Pi Connectivity: Standard 40-pin GPIO header for a direct, secure connection.
- Native USB Access: A dedicated USB-C port connects directly to the mosaic-G5's USB hardware for high-speed data access.
- Mounting Hardware Included: Includes the necessary standoffs, screws, and an extended header for secure assembly.
Miniaturized Precision with mosaic-G5
At the heart of this kit is the Septentrio mosaic-G5, a receiver that delivers the same performance as the mosaic-X5 but in a 60% smaller package that consumes 40% less power.
- Millimeter-Level Accuracy: Delivers 6mm horizontal and 1cm vertical accuracy with RTK.
- Precise Timing: Features a PPS timing resolution of 1.4ns and event-trigger accuracy <3ns, making it ideal for exact time-synchronization applications.
- AIM+ Interference Mitigation: Equipped with Septentrio's AIM+ technology, offering best-in-class protection against jamming and spoofing to ensure reliability in hostile RF environments.
- Multi-Band & Multi-Constellation: Tracks all signals from all major constellations (GPS, GLONASS, Galileo, BeiDou, QZSS) simultaneously.
Configuration & Advanced Control
The mosaic-G5 offers professional-grade control and configuration for advanced users.
- Flexible Protocols: Supports industry-standard NMEA, RTCM v3.x, and the highly efficient Septentrio Binary Format (SBF).
- Sophisticated Software: Configure and monitor the module using Septentrio's RxTools suite or via a robust Command-Line Interface (CLI) over USB or Serial.
- Interfaces: Access two hardware UARTs, two GPIO pins, two PPS outputs, and two Event inputs through the pHAT's headers.
- RTK Base functionality due Q2 2026: The initial mosaic-G5 P3 firmware does not support RTK Base and it can not generate RTCM corrections. Septentrio will add base station capability to the mosaic-G5 P3 and P3H in a firmware release currently planned for the Q2 2026.
This product requires an external multi-band antenna. Users have a few options for connecting an external GNSS antenna to their GNSS receiver.
- The GNSS Flex module has a U.FL connector for an external antenna.
- For a sturdier connection, the SparkFun GNSS Flex pHAT includes an SMA connector bridged to a U.FL connector. Users simply need to jumper the U.FL connectors on both the SparkPNT GNSS Flex module and SparkFun GNSS Flex pHAT with a short U.FL cable.
This pHAT also requires a Raspberry Pi (or similar single-board computer). Users can find Raspberry Pi and NVIDIA single-board computers in our catalog. By default, we use the Raspberry Pi's primary serial bus (i.e., TX: GPIO14/Pin 8; RX: GPIO15/Pin 9) to communicate with the GNSS receiver of the SparkPNT GNSS Flex module. However, users can also utilize any of the other interfaces.
