Issue with noise spurious on z Component measurement

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MMductance
Level 2
Level 2
5 sign-ins First solution authored First like received

Hello everyone

I am using the W2BW 3 axis hall sensor from the 2go kit and I am picking up some spurious noise on the magnetic field z Measurement. The Figures below show a measurement from a sensor when a parmanent magnet is held toward the sensor six times. As can be seen, while the x and y measurements seem to be clean, there is some spurious noise on the z component.

I thought it might be crosstalk from the I2C communication but I'm not sure.

I am setting the sensor to Master-Controlled Mode and issue an I2C read command at a frequency of 500Hz using the 1-Byte Protocol.

I set the trigger mode in the CONFIG register to 10 (e.g. ADC trigger should be after register 0x5H has been sent).

I also attached an image of the I2C waveform. On the lower graph. 

Sensor OutputsSensor OutputsSensor Outputs (Bz Zoomed In)Sensor Outputs (Bz Zoomed In)

W2BW_DEBUG.png

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1 Solution
MMductance
Level 2
Level 2
5 sign-ins First solution authored First like received

Hello

The issue seemed to be the I2C module of the uC that I was using and not the sensor. I was able to resolve the issue in the meantime.

View solution in original post

2 Replies
Yaran_W
Moderator
Moderator
Moderator
250 replies posted 100 solutions authored 25 likes received

Hi MMductance,

I don't think  the noise is caused by I2C data transmission, because data transmission will also affect the X and Y axes.

Maybe you can check whether there is a problem with the data at the input side of sensor.

Or analyze whether the noise spectrum matches the 500Hz you give.

Best Regard!

Yaran

MMductance
Level 2
Level 2
5 sign-ins First solution authored First like received

Hello

The issue seemed to be the I2C module of the uC that I was using and not the sensor. I was able to resolve the issue in the meantime.