JAJSMO7D August 2021 – September 2022 TMAG5231
PRODUCTION DATA
Due to the complex non-linear behavior magnets and the number of variables that can influence it, some experimentation is required to solve for a design that will work. This application uses a simple axial, dipole, block magnet. Other shapes might be considered for different field strengths or prices. A neodymium type of magnet (N52) is used. At the time of this writing, N52 can be commonly found with heights of 1/16", 1/8", 3/16", and 1/4". As price often increases with size, the first design attempt will be with a 1/16" thick magnet, which has a width and length equal to 0.25". Based on the sensor distance from hinge origin and fixture dimension constraints, there is a lot of flexibility on where the sensor can be placed. Due to other hardware within the fixture, the TMAG5231B1DQDBZ sensor is placed 8" (203.2 mm) from the origin. From there, the user can assess a design with the following displacement dimensions.
Figure 9-4 shows that the b-field magnitude for the TMAG5231B1DQDBZ is not adequate for the spatial constraints of 5° and 15°, as the Bz magnitude only surpasses the BRP minimum. There are a few options on how to proceed. As the BOP(Max) does not fall within our range,the user must increase field strength. This can be accomplished with a thicker magnet or by adjusting sensor and magnet z-offsets. The magnet cannot get any closer due to enclosure constraints, therefore the only option allowed is to increase the magnet thickness. After a few more iterations with the tool, a 0.25" × 0.25" × 0.25" magnet can work (see Figure 9-5 and Figure 9-6).