Hall Sensor testing

Thread Starter

viju

Joined Sep 28, 2008
120
Could some one suggest me a method to test the hall sensor as per the specifications below,

1. Hall sensor should be subjected to 23mT and test for ON
2. Hall sensor should be subjected to 9mT and should remain ON
3. Hall sensor should be subjected to -23mT and test for OFF
4. Hall sensor should be subjected to -9mT and should remain ON

How should I create a varying magnetic field?
I tried with low hysteresis steel rod wrapped coil around it and energized it with voltage controlled
current source to vary the current.I measured the gauss level using a linear hall sensor w.r.t current applied.
But when the rod is placed near the hall sensor ( DUT ), it does not behave as per the specification.
I tried with different hall sensors in the lot but the result was same.

Please suggest me
1. How to create magnetic field as per the specification and equation related to it
2. How do you I verify the generated magnetic field

Viju
 

Dodgydave

Joined Jun 22, 2012
11,395
I would wrap enamel cooper wire around a cardboard tube, like a toilet roll, full-length the size of wire is upto you, put a constant current through the coil say 100ma to 1 amp, this will give you a magnetic field,different current will give different field strength.
 

Thread Starter

viju

Joined Sep 28, 2008
120
I would wrap enamel cooper wire around a cardboard tube, like a toilet roll, full-length the size of wire is upto you, put a constant current through the coil say 100ma to 1 amp, this will give you a magnetic field,different current will give different field strength.
I did wrap enamel copper wire and tried with different current combination. I too measured the gauss level for a particular current in which hall sensor would latch.But I ended up in fail as the gauss level and hall sensor switch over does not have relationship.
 

Alec_t

Joined Sep 17, 2013
15,118
the method of creating magnetic field
... is as stated in post #2. If the coil length is at least 5 times its diameter then B = µNI/L, where B is flux density in Tesla, µ = 4π x 10-7, N = number of turns, I = current (in Amps), and L = coil length (in metres).
 

Kermit2

Joined Feb 5, 2010
4,162
i would suggest a gapped toroid shape. this ensures the field is not curved as it tries to return to the opposit end of the solenoid. also incorporate the area of the hall effect device as the size of the area needing the field strength stated when you calculate turns and current. a coil with a larger area will need more field strength over that area to generate the called out intensity across the smaller area of the DUT.
 
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