Honeywell Surface Mount Hall Effect Sensor, SOT 23, 3-Pin

The Honeywell SM351RT magneto resistive sensor ICs (integrated circuits), standard power series, are ultra-sensitive device designed for manufacturers who need a durable and reliable speed or position sensor for large air gaps or small magnetic fields in standard power (typically 3 Vdc to 24 Vdc) applications. Unlike reed switches and other magnetic sensors and solid state design offers ultra-high sensitivity of 11 G max, making it the highest sensitivity sensor in its class for standard powered applications.

Omnipolar sensing activates with either pole from a magnet
Temperature range -40 °C to 85 °C [-40 °F to 185 °F]