Testing on analog hall sensor 49E

 

Testing is done with an arduino, connect 5V,GND to hall sensor, hall sensor out put is connected to ADC A0.

stick the hall sensor with face to magnet one side will 0, the other one is 1024.

Set up like pics.




The reading is 0 when you please the magnet is too close, such as in the range of 3mm, when range reaching 20mm, the reading is 498, almost getting lost.



The chart of testing data shows:

1. the slop is not a constant.

2. it shows a curve, so if I want to use hall sensor to sense the distance, there is a range of best resolution.

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