Solid State Magnetometers
Page Under Construction
This page describes the types and some of the theory about solid state magnetic sensing
Types
-Hall Effect
-AMR
Hard Axis/Easy Axis
-GMR
-SDT
Sources of Error
-Thermal offset
-Cross axis
-External
-Bridge Offset
--Manual Trim
--Offset Strap
--Digital Subtraction
--Electronic Feedback
Noise
-1/f
-Barkhausen
-White/thermal (Johnson?)
Links! Lots of Lovely Links.
TO DO: sort out the good stuff
Much more to come
Recomended Links
Describes the physics and construction of an AMR sensor Magnetoresistive Sensors (Hauser, Stangl, Fallmann, Chabicovsky, & Riedling | 2000?)
Excellent article on AMR sensors and their operation from SensorsMag (see the electronic feedback and closed loop sections)
Comparison of AMR and Hall sensors from SensorMag
Introduction to many types of magnetic sensing including solid state, SQUID, fluxgate, etc. From SensorsMag
Vendors
AMR:Honeywell(TO DO: Go through application notes) We will probably be using sensors from this company. Everything below is somewhat useless, although they may have good application notes
AMR/GMR:Sensitec (Do they have anything interesting?)
AMR:NXP It looks like they stopped making weakfield sensors, but the ANs are good
GMR/SDT:NVE
Hall/AMR:iC-Haus
AMR:HL-Planar Technik Has same part numbers as NXP?
AMR(?):Yamaha 3-axis aren't out yet?
Hall:Asahi Kasei EMD They had a 3-axis geomagnetic sensor but I can't find it now.
Hall:Micronas Probably not useful
Hall:Allegro
Hall interface:Maxim
Hall:Infineon
Other Links
General information on all types of magnetic stuff Brooke's Sensors page(need to read it and find relevant information)
Random PSAS wiki page with links (move to better area?)Random Wiki magnetometer page
A magnetometer discussion page and group, has some designs and links to other pages The Magnetometer Group (To Do: examine their discussion group)
Wikipedia page on Magnetoresistance (not very good) Magnetoresistance
An example of an electronic compass for use in robots
Fully functional micro-compasses from Ocean Server
GMR Lowfield sensing overview from SensorMag (need to find part 2)
Mailing Lists
OpenMoko brief discussion on using a magnetometer for use in a cellphone Try to find if they came up with anything?
OpenAHRMS Discussion more