Team,
It seems that a comparable magnet is used in the SLYA036A (+ video) and in the DRV5055-ANGLE-EVM board (see below pictures).
However the DRV5xxx sensor is placed differently:
-Can you please explain the differences?
-What is the best placement and for which use case?
-I saw an E2E post mentioning the FEMM tool. Does it help to choose the best sensor/magnet orientation ?
-SLYA036A (+ video):
-DRV5055-ANGLE-EVM:
Thanks in advance,
A.
Hello AnBer,
Here are my responses to your questions:
1) The picture you provided from the SLYA036A document shows two TO-92 packages 90° apart from each other with the main sensing direction facing the magnet. When using the TO-92 package, this is the most common way to place the sensors because you utilize the strongest field direction of the magnet. For the EVM, the sensors were placed sideways (see Hall4 and Hall2 from image below) so that they could be used in conjunction with the SOT-23 sensors under the magnet (Hall1 and Hall3 from the image below).
This means that for the EVM, you can detect the 360° angle using any of the following sensor combinations:
Hall1 and Hall3
Hall2 and Hall4
Hall1 and Hall2
Hall3 and Hall4
2) Generally speaking, when using the TO-92 package, you would want to use the placement from the SLYA036A document, as those sensor orientations utilize the strongest field from the magnet. The orientation for the TO-92s in the EVM could still be used if your system space requirements needed it. You also may want to consider using the SOT-23 orientation from the EVM for a more compact design if your system allows it.
3) The FEMM tool can help you verify the strength of the magnet versus the sensor position (distance away from magnet) and sensor sensitivity to make sure that your sensor output will not get railed or to see if you are using enough of the sensor dynamic output range.
