Dear all,
I have started testing DRV5053 for position sensing application, where I'm hoping it (or a pair of them) could help me understand where I am on a 20mm scale with at least +/-1mm precision and 5mm away from the magnet. While this the first thing I'm doing with analog hall sensors (have used digital on many projects) and I'm only in the very beginning in understanding if this is a solution to the problem at all, I'm encountering the first issues I do not quite understand and would be glad about some help.
First and foremost is Vq. It looked suspicious on the ADC result of MCU, but a simple multimeter confirms I have about 1.50V Vq on the device with no magnets around. I have tried to move it, to change the power supply to a different voltage, to hang it in a cable away from the desk and three different versions of DRV5053 (different sensitivity) and I get the same result. The temperature is not some 150C either - it is normal 'room temperature' or about 21C. How come if the data sheet says Vq should be 1.00V +/- a little bit?
Second, I'm using all sorts of magnets for testing, but even the largest of them might seem small to many - 10mm neodymium button magnet. Is it possible that I cannot sense a change in magnetic field from N to S even a few mV large with this sort of magnet? I mean, one on each side of my index finger are sort of painful :).
Thank you for your input,
Edmunds