Two Approaches to Magnetic Field Detection
Both reed switches and Hall effect ICs detect magnetic fields, but their operating physics dictate vastly different circuit requirements.
Reed Switches (Passive Mechanical)
- Zero Power Consumption: Consumes 0.0µA in open state — ideal for battery-operated IoT door and window sensors.
- Immune to Electrical Noise: Pure metallic contact without semiconductor drift.
- High Voltage Switching: Can directly switch up to 200V AC/DC loads.
Hall Effect Sensors (Solid-State Semiconductor)
- Unlimited Mating Cycles: No mechanical fatigue; ideal for high-RPM motor encoders.
- Continuous Current Draw: Requires active DC bias supply.
- Bipolar / Latching Options: Can differentiate between North and South magnetic poles.