TFRPMMAG01 - Magnetic RPM Sensor with I2C Interface
The TFRPMMAG01 is a compact sensor designed for measuring the RPM of diametrically magnetized rotating parts, primarily in UAV and drone applications. It supports direct connection to Pixhawk-based autopilot systems with PX4 firmware. The high-speed measurement capability and compact design make it a robust solution for UAV propulsion monitoring and general rotary speed sensing.
Features
- Designed for UAVs: Compact round form factor optimized for drone integration
- High-Speed Measurement: Accurate up to 28,000 RPM
- I2C Interface: Simple connection to autopilots and controllers
- Pixhawk Compatibility: Plug-and-play support with PX4 firmware
- High Resolution: 14-bit precision for accurate RPM detection
Where to Buy?
The TFRPMMAG01 is available from ThunderFly s.r.o..
For a quotation or support, contact us at sale@thunderfly.cz.
Technical Specifications
| Parameter | Value | Description |
|---|---|---|
| RPM Measurement Principle | Diametrically magnetized rotating part | Ensures dust-reliable speed detection |
| Max. Operating Speed | 28,000 RPM | High-speed UAV and motor applications |
| Resolution | 14-bit | Provides precise RPM and position data |
| Interface | I2C | Standard 4-pin JST-GH connector |
| I2C Address | 0x40 | Default address, configurable in PX4 |
| Input Voltage | 3.3 – 5 V | Supports common Pixhawk UAV bus voltages |
| Connector | JST-GH 4-pin | Pixhawk standard Pixhawk pinout |
| Dimensions | 18 × 18 × 5 mm | Compact circular PCB |
| Mass | 2 g | Without cable |
Pin Configuration
Interface conforms to the Pixhawk Connector Standard.
| Pin | Name | Type | Description |
|---|---|---|---|
| 1 | VDD | Power | Power supply (3.3–5.5 V) |
| 2 | SCL | Input | Serial Clock Line (I2C) |
| 3 | SDA | I/O | Serial Data Line (I2C) |
| 4 | GND | Ground | Ground connection |
Design and Functionality
The sensor detects RPM by measuring the rotation of a diametrically magnetized part. Its compact design allows for direct mounting in UAV propulsion systems. An indicator LED provides a visual pulse once per revolution, aiding in testing and calibration.
Place a diametrically magnetized disc magnet above the sensing area on the TOP side and keep it centered. Maintain a small axial air gap and avoid axial magnetization. Any rotation angle is acceptable; RPM is derived from the change of angle over time.
PX4 Autopilot Integration
The PX4 firmware includes support for the TFRPMMAG01. When connected to the I2C bus of a Pixhawk flight controller, it is automatically detected and can be configured through standard PX4 parameters.
Applications
- UAV propulsion monitoring
- RPM measurement in BLDC motor systems
- General-purpose rotary speed sensing