Description:
Hall-effect sensors are commonly used for measuring the speed of rotating assemblies where a magnet on the assembly alternately makes and breaks magnetic contact with the sensor as the assembly rotates.  They can also be used for applications such as determining when a door has been opened, position sensing and detecting the magnetic field created by current flow in a wire.
Senses relative strength of magnetic field and provides analog voltage output.
Can differentiate between North and South pole of magnet
3.3 and 5V compatible
Analog Output
The sensor output is an analog voltage. When no magnetic field is detected, the output will rest at approximately 1/2 Vcc. If the south pole of the magnet is brought near, the output will linearly ramp towards Vcc and if the north pole of the magnet is brought near, the output will linearly ramp towards ground.
In the case of Vcc being 5V, with no magnetic field present the output will rest at about 2.5V. If the south pole of the magnet is brought near, the output will raise linearly up to a maximum of about 4.2V. If the north pole is brought near, the output will lower linearly to a minimum of about 1.0V.
The output is typically read by an ADC port on a uC if the strength or pole of the magnetic field is important. Optionally it can be run into a comparator like the LM393 if a digital output with an adjustable set-point is desired. If you are just counting the number of times a magnet goes by, this is easier than working with the analog output. Digital Hall-effect sensors are also available for this purpose.
Model: 49E
Package: TO-92
Number of Pins: 3
Voltage Supply: 3V~6.5V
Operating temperature range: -40°C ~ +100°C
Package included:
10pcs 49E OH49E SS49E Linear Hall Effect Magnetic Sensor Switch Arduino