Magnetic sensing shows up almost anywhere something needs to be measured without physical contact — position, speed, current, or proximity. But “magnetic sensing solutions” spans a wide range of technologies, each suited to a different combination of accuracy, environment, and cost. Here’s how to tell them apart and what to look for in a supplier.
The Core Magnetic Sensing Technologies
- Hall Effect sensors — measure magnetic field strength directly via voltage output; low cost, widely used for proximity and current sensing, but generally lower precision than magnetoresistive alternatives.
- AMR (Anisotropic Magnetoresistive) sensors — more sensitive than Hall Effect, common in compass and low-field detection applications.
- GMR (Giant Magnetoresistive) sensors — higher sensitivity and signal output than AMR, often used in high-precision position and speed sensing.
- TMR (Tunnel Magnetoresistive) sensors — the highest sensitivity of the group, increasingly used in angle sensing and current sensing where AMR/GMR fall short.
- Magnetic encoders — combine a magnetic sensor with a rotating or linear magnetic scale to output precise position or speed data (see our related guide on encoder selection).
What Determines the Right Sensing Technology
- Required resolution and accuracy — TMR and GMR sensors resolve smaller field changes than Hall Effect, but cost more and can be more sensitive to noise.
- Operating temperature range — sensor drift and accuracy both shift with temperature; confirm the manufacturer’s rated performance across your actual operating window, not just room temperature.
- Air gap tolerance — the distance between sensor and target magnet affects signal strength; each technology has a different practical air gap limit.
- Output type — analog, digital, or communication-protocol output (SPI, I2C, PWM) needs to match your control system architecture.
- Environmental sealing and EMI immunity — critical in automotive, industrial, and outdoor applications where vibration, moisture, and electromagnetic interference are present.
Common Applications
- Motor commutation and speed feedback
- Current sensing in power electronics
- Automotive position and proximity sensing (throttle, pedal, steering angle)
- Industrial proximity and object detection
- Linear and rotary position measurement in robotics and automation
Sourcing a Magnetic Sensing Supplier
Sensor selection is rarely a catalog decision — the right technology depends on your field strength, air gap, and environmental conditions, and the wrong choice shows up as noise, drift, or premature failure in the field. Working with a supplier who understands the underlying magnetics, not just the sensor IC, tends to save significant rework later. The Magnetics Professional directory lists sensor and component manufacturers with demonstrated magnetics engineering capability, making it a more targeted starting point than a general electronics component search.