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Method for calculating magnetic field intensity from a magnetic sensor's output values

 

This section explains about analog sensor output.

(→link Digital case)

 

For an analog sensor, whether you measure the output voltage yourself with a voltmeter or use an AD converter, you must convert to digital.

 

(1) When measuring with a voltmeter

When measuring with a voltmeter, calibrate that result and find the sensitivity and origin.

(→link Calibration method)

 

Magnetism = (measured voltage - origin) / sensitivity

 

Using the above formula, you can find the measured value of magnetism.

 

(2) When measuring using an AD converter

When measuring using an AD converter, the AD converter’s input voltage is converted to a digital value, the accuracy of which depends on the grade of the converter.

convert1

Even when using the AD converter's measurement, the sensitivity and origin can be calculated from the voltage in the same way.

When looking for sensitivity a and origin b, magnetism can be calculated as follows.

 

Magnetism = (AD output value - origin) / sensitivity