Gaussmeter with .01 gauss resolution

Thread Starter

gjo

Joined May 22, 2013
43
I've been trying to design a gaussmeter circuit with a hall effect sensor that has .01 gauss resolution. But, I cannot find a hall sensor that fits this criteria. If anyone can help suggest a hall sensor and the circuit layout that would work with it Greatly appreciate any help.
 

MrSalts

Joined Apr 2, 2020
2,767
0.1 gauss = 1 microTesla.
What range are you looking at? If you want +/-1 milliTesla range with a 12 to 16-bit resolution, you will have your 1 microTesla resolution.


DatasheetImageDK Part #Mfr Part #MfrSupplierDescriptionStockPrice@ qtyMin QtyPackageSeriesPart StatusTechnologyAxisOutput TypeSensing RangeVoltage - SupplyCurrent - Supply (Max)Current - Output (Max)ResolutionBandwidthOperating TemperatureFeaturesSupplier Device PackageMounting TypePackage / Case
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-010-SP-NDMLX90392ELQ-AAA-010-SPMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 5MT 8UTDFN2002.8201TubeTriaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-011-SP-NDMLX90392ELQ-AAA-011-SPMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 50MT 8UTDFN1752.8201TubeTriaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-010-RETR-ND,413-MLX90392ELQ-AAA-010-RECT-ND,413-MLX90392ELQ-AAA-010-REDKR-NDMLX90392ELQ-AAA-010-REMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 5MT 8UTDFN9,9372.9401Tape & Reel (TR),Cut Tape (CT),Digi-Reel®Triaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-011-RETR-ND,413-MLX90392ELQ-AAA-011-RECT-ND,413-MLX90392ELQ-AAA-011-REDKR-NDMLX90392ELQ-AAA-011-REMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 50MT 8UTDFN9,9692.9401Tape & Reel (TR),Cut Tape (CT),Digi-Reel®Triaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
 

Thread Starter

gjo

Joined May 22, 2013
43
0.1 gauss = 1 microTesla.
What range are you looking at? If you want +/-1 milliTesla range with a 12 to 16-bit resolution, you will have your 1 microTesla resolution.


DatasheetImageDK Part #Mfr Part #MfrSupplierDescriptionStockPrice@ qtyMin QtyPackageSeriesPart StatusTechnologyAxisOutput TypeSensing RangeVoltage - SupplyCurrent - Supply (Max)Current - Output (Max)ResolutionBandwidthOperating TemperatureFeaturesSupplier Device PackageMounting TypePackage / Case
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-010-SP-NDMLX90392ELQ-AAA-010-SPMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 5MT 8UTDFN2002.8201TubeTriaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-011-SP-NDMLX90392ELQ-AAA-011-SPMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 50MT 8UTDFN1752.8201TubeTriaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-010-RETR-ND,413-MLX90392ELQ-AAA-010-RECT-ND,413-MLX90392ELQ-AAA-010-REDKR-NDMLX90392ELQ-AAA-010-REMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 5MT 8UTDFN9,9372.9401Tape & Reel (TR),Cut Tape (CT),Digi-Reel®Triaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
https://mel-prd-cdn.azureedge.net/-...ll-non-automotive-selection-guide-melexis.pdf//media.digikey.com/Photos/Melexis%20Photos/MFG_MLX90392series.jpg413-MLX90392ELQ-AAA-011-RETR-ND,413-MLX90392ELQ-AAA-011-RECT-ND,413-MLX90392ELQ-AAA-011-REDKR-NDMLX90392ELQ-AAA-011-REMelexis Technologies NVMelexis Technologies NVSENS MAG I2C TRIAXIS 50MT 8UTDFN9,9692.9401Tape & Reel (TR),Cut Tape (CT),Digi-Reel®Triaxis®ActiveHall EffectX, Y, ZI²C0 ~ 5mT, 5 ~ 50mT1.8V1mA-16 b1.4kHz-40°C ~ 85°C-8-UTDFN (2.5x2)Surface Mount8-XFDFN Exposed Pad
Looking for 1 to 800 gauss range with a dc power source.
 

Thread Starter

gjo

Joined May 22, 2013
43
I just want to use the meter to measure changes in a dc electromagnet that I built.
Does allegro or anyone else sell ratio metric hall sensors with .01 gauss linearity and a range between 1 and 800 gauss?
 

DickCappels

Joined Aug 21, 2008
10,153
A differential Hall sensor might do it but you might need to filter out some noise and somehow take care of the drift for it to work.

https://www.imperial.ac.uk/space-an.../fluxgate-magnetometers/how-a-fluxgate-works/

Fluxgate Magnetomiters:
These things can be very sensitive. One company I worked for used them to detect changing magnetic fields so the monitor would automatically degauss itself, for example if it were rotated on a desk. The only thing was that it was so sensitive that if you opened a drawer in your cubicle the monitor would degauss. The monitors were built by Philips-Fimi in Italy. There was a railroad that ran along the length of the factor. As trains went by every monitor in the factor would degauss itself. It seems LCDs don't have a need for that function.
 

MrSalts

Joined Apr 2, 2020
2,767
A differential Hall sensor might do it but you might need to filter out some noise and somehow take care of the drift for it to work.

https://www.imperial.ac.uk/space-an.../fluxgate-magnetometers/how-a-fluxgate-works/

Fluxgate Magnetomiters:
These things can be very sensitive. One company I worked for used them to detect changing magnetic fields so the monitor would automatically degauss itself, for example if it were rotated on a desk. The only thing was that it was so sensitive that if you opened a drawer in your cubicle the monitor would degauss. The monitors were built by Philips-Fimi in Italy. There was a railroad that ran along the length of the factor. As trains went by every monitor in the factor would degauss itself. It seems LCDs don't have a need for that function.
And emphasizes my question, do ya really need 1uTesla resolution?
 

Thread Starter

gjo

Joined May 22, 2013
43
I appreciate all the responses. I'm looking to replicate Alpha labs Dc gaussmeter:
DC Gaussmeter Model GM1-HS


The Gaussmeter Model GM1-HS reads moderate-strength static magnetic fields up to 800 G with a resolution of 0.01G. It measures magnetization of ferrous metals, solenoids and the far field of strong magnets
 

Deleted member 115935

Joined Dec 31, 1969
0
A few thoughts ,

the sensor graph, shows 500 mV for 200 Gauss change,
If I have it right, that 2.5 mV per Gauss
or 25 uV for 0.01 gauss
A lot of chance of noise there,

What sort of thing can cause 0.01 Gauss change, the current in the wires to the sencor ?
metal in the case / probe ?

Have you checked the accuracy / stability over PVT , as opposed to just the resolution,
 

MrSalts

Joined Apr 2, 2020
2,767
A few thoughts ,

the sensor graph, shows 500 mV for 200 Gauss change,
If I have it right, that 2.5 mV per Gauss
or 25 uV for 0.01 gauss
A lot of chance of noise there,

What sort of thing can cause 0.01 Gauss change, the current in the wires to the sencor ?
metal in the case / probe ?

Have you checked the accuracy / stability over PVT , as opposed to just the resolution,
The 0.01 gauss is likely a number he pulled out of his _ _ _. He is measuring a magnet he made in his lab. He's not measuring temporal changes to magnetic North Pole from his office in Tacoma.
 
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