I am not sure if this is the right category for this sensor. This is the closest I have found in the available categories.
I am trying to use the AD22151 Hall Effect sensor. I am however having trouble understanding the gain and offset settings for the sensor.
The data sheet is at http://www.analog.com/static/imported-files/data_sheets/AD22151.pdf and the gain and offset settings are described on page 5/8.
To start, the Offset is supposed to be 1 + (R3 / R2 + R4) * (Vcc - Vout). Why does Vout factor into the offset? Shouldn't the offset be consistent over the range of output from the hall-effect sensor?
Even in the example calculation for R3/R2 and R4, part 4 shows ((Vcc / 2) - 1) / Vcc = 0.375, but with Vcc = 5V (which is what the example is using), that equation should equal 0.3, not 0.375.
Am I missing something? I am trying to make the sensor be unipolar and operate in the range ~0-350G.
Any help would be greatly appreciated.