The 2D magnetic field strength in x- and z-direction was measured at a 4kHz sample rate with the trigger mode enabled to dump 200 consecutive samples. Figure 4-6 shows the measured x- and z-axis data over the absolute linear position measured with the reference position encoder.

When analyzing the captured data, we see that the X and Z component data observed by each TMAG5170 sensor overlapped. The z-axis has unipolar range and can be approximated within ±90 degree to a cosine signal with an offset equal to the amplitude. The X-axis has a bipolar amplitude, and can be approximated within ±90 degree to a sine signal. Due to that, the full-scale magnetic range for each TMAG5170 is set to ±50mT for the Z-axis and ±25mT for the x-axis.

The reason for the declining Z field amplitude from the first to the last TMAG5170 is since the TIDA-060045 PCB was not exactly mounted parallel to the mounting plate and the airgap slightly increased from the first TMAG7170 to the last. This mechanical calibration was not done.

Figure 4-7 and Figure 4-8 show the time domain plot of 1000 consecutive samples of the X-field and Z-field measured with the first TMAG5170 at a 4kHz sample rate. For this test the absolute position of the sense magnet was 14.19cm.

Figure 4-9 and Figure 4-10 show the corresponding histogram of the X-field and Z-field data.

The standard deviation, signal-to-noise ratio (SNR) and effective number of bits (ENOB) versus full-scale range are shown in Table 4-4. The noise in the X-axis dominates due to the higher gain setting with the TMAG5170 X-axis.