TMAG6180-Q1: What's the difference between AMR and TMR

Of the magnetic sensing technologies, TMR is the most sensitive.  TMR, AMR, and GMR are all sensitive to the direction of the magnetic field, which can make them useful in detecting angle.  Of the three, only AMR is limited to 180 degree rotation by itself since it will produce two full periods on the output per revolution of the magnetic field.   TMR does tend to experience elevated noise, but has a very low current consumption.  This technology involves multiple layers of ferromagnetic material which make the process more expensive typically. Also, since there are ferromagnetic materials, this technology can be damaged by exposure to magnetic fields above a maximum threshold.

AMR is very low noise, and not subject to damage due to strong fields.  Given this, is can compete well against TMR if the 180 degree limitation can be addressed.  TMAG6180 integrates a 2D Hall-effect latch to determine rotation quadrant which removes ambiguity when calculating angle.  

The TAS2143 Datasheet doesn't offer a lot of detail about device performance outside of the angle accuracy, which is comparable to TMAG6180.  It is likely that TMAG6180 could replace TAS2143 if the customer MCU can support the GPIOs required to monitor the Q1 and Q0 pins.