SparkFun GPS-16329 NEO-M8U GPS Dead Reckoning Breakout (Qwiic)

SparkFun's GPS-16329 breakout carries the u-blox NEO-M8U, a GNSS receiver with a built-in accelerometer and gyroscope that keeps estimating position through tunnels, parking structures and urban canyons when satellite signals drop out. It suits rovers, ground robots, vehicle trackers and experimental UAV navigation where a position gap is unacceptable, and plugs into any Qwiic or I2C host without soldering.

Key features

• Untethered Dead Reckoning fuses IMU data with GNSS, so it needs no wheel-tick or vehicle connection
• 72-channel receiver for GPS, GLONASS, Galileo and BeiDou, tracking up to three constellations concurrently
• Position updates up to 30 Hz with 2.5 m horizontal accuracy
• I2C over Qwiic plus UART on 0.1-inch breakout pins, with NMEA, UBX and RTCM protocols
• On-board rechargeable backup battery keeps the RTC and orbit data for 1.5 s hot starts
• Geofencing, odometer and spoofing detection built into the receiver

Specifications

• GNSS module: u-blox NEO-M8U
• Channels: 72
• Constellations: GPS, GLONASS, Galileo, BeiDou
• Horizontal accuracy: 2.5 m
• Velocity accuracy: 0.5 m/s
• Heading accuracy: 1 deg
• Max update rate: 30 Hz
• Time to first fix: 26 s cold, 1.5 s hot
• Time pulse accuracy: 30 ns
• Operating limits: 50,000 m altitude, 500 m/s, 4 g
• Interfaces: I2C (Qwiic), UART
• Supply: 3.3 V VCC and I/O, about 29 mA while tracking
• Antenna connector: U.FL

No antenna is included: pair it with a GNSS antenna on a U.FL lead or a U.FL-to-SMA pigtail. The board runs 3.3 V logic, so use a level shifter when wiring the UART to a 5 V microcontroller, and mount it rigidly, as the dead-reckoning solution relies on the IMU staying fixed to the chassis.