Matek ASPD-4525 Digital Airspeed Sensor, MS4525DO I2C

The Matek ASPD-4525 is a digital airspeed sensor for fixed-wing and VTOL aircraft running ArduPilot, INAV or PX4. Built around the MS4525DO differential pressure sensor, it gives the autopilot measured airspeed over I2C instead of relying on GPS ground speed — which matters for stall margins, auto-throttle and wind estimation.

Key features

• MS4525DO sensor with a 1 PSI (6.89kPa) differential range and ±0.25% span accuracy
• I2C output on a 4-pin JST-GH connector wired 5V, SCL, SDA, GND — the Pixhawk-standard I2C pinout
• Runs from 4–5.5V at 5mA, with a red power LED
• Rated from -40°C to 125°C, with a 20 PSI maximum pressure
• Kit includes the pitot tube, 40cm clear silicone tubing and a 20cm JST-GH 4-pin cable

Specifications

• Sensor: MS4525DO
• Supply voltage: 4–5.5V DC
• Current draw: 5mA
• Interface: I2C (SCL, SDA)
• Pressure range: 1 PSI (6.89kPa)
• Maximum pressure: 20 PSI (137.9kPa)
• Accuracy: ±0.25% span
• Operating temperature: -40°C to 125°C
• Connector: JST-GH 4-pin (5V, SCL, SDA, GND)
• Weight: 3.5g (sensor board)
• In the box: Sensor board, pitot tube, 40cm silicone tubing, 20cm JST-GH 4-pin cable

Mount the pitot tube clear of the propeller wash and route the tubing without kinks. On INAV, skip versions 3.0.0 and 3.0.1, which had a known airspeed-sensor bug — use 3.0.2 or later.