Magnetic sensor characterization techniques

[Guille]

Hi everyone,

We are a team of researchers collaborating with another team that produces magnetic sensors (AMR and TMR Wheatstone Bridges) we are tasked with characterizing said sensors but since we are physicists this area is not our forte. I'm therefore looking for good resourcess on sensor characterization (magnetic sensors if possible), how can one find what the industry standard for this task is? Experimental setup, proceedings, figures of merit...

If hard to find books, lectures, application notes, etc are great recommendations too.

Thank you for your time!

[Conrad Hoffman]

I don't know if there are general standards. When I've had to characterize magnetic sensors I use a stepper driven stage (Velmex or similar) and mount the sensor or magnet on the stage. I write test programs to sweep the sensor past the magnet (or rotate if that's what you need) and collect data at whatever increments are needed. There are some tricks you can use like opposed magnets to create a narrower field. Honeywell had a useful book on hall effect devices that you can download here- https://www.rsp-italy.it/Electronics/Databooks/Honeywell/_contents/Honeywell%20-%20Hall%20Effect%20Sensing%20and%20Application%201998.pdf

[Guille]

We tried measuring Sensitivity and Detectivity of commercial sensors however these measurements differed greatly from the datasheet specs which makes me wonder if we are doing something wrong and thus are not ready to characterize the sensors our colleagues are developing

[Conrad Hoffman]

It's nice to have a reference point- do you have a gaussmeter? I use an F.W. Bell unit that's decent as they have some tiny probes that suit my tiny projects. 

[3roomlab]

what about making the helmhotz coil ?
like using it to transfer a reference
a known unit can measure it
and then the unknown unit ?