DRV5055: Customer needs version of this part that is more "sensitive"

Hello Daniel,

There are a couple options based on how much more sensitive you need the device. The suggestions I will give below presume that you need a  linear output, and not a switch or latch output. 

The DRV5055A1 is a bipolar linear Hall device with a gain of 100 mV/mT.  This is the most sensitive version of this device. The DRV5056A1  is a unipolar linear Hall device with a gain of 200 mV/mT. If it works in your system, you can put two DRV5056A1 devices back to back (ie, one on either side of the PCB with the DBZ package), and use one sensor when the field is in one direction, and the other sensor when the magnetic field is reversed.  Doing this will double the gain of your current setup.  You can also filter the outputs or averages samples to help reduce noise and increase measurement accuracy. 

If you need a significantly more sensitive device, you could switch from a Hall effect sensor to a fluxgate sensor.  The DRV425 is a fluxgate sensor that is a highly accurate and highly sensitive device with a linear output based on the strength of a magnetic field.  This device has a maximum full scale measurement range of ±2 mT (as opposed the the ~±20 mT range of the above solution)