Significant characteristic of our Hall probes is high linearity of the output voltage change for a change of the magnetic flux density. Typical linear characteristic of LHP-NP Hall probe measured at temperature 4.2 K is plotted on Figure 1. Actual measured data from the graph are highlighted in the table. It is evident precise relationship between the ideal curve (linear fit) and actual measured data (Hall voltage). Benefited from this superior performance, majority of our customers rely on the linear output characteristic and do not require the calibration.

 

Calibration 1Calibration 2

 

Figure 1. Typical linear characteristic of the Hall probe and table of actual measured data

 

In spite of this, in some specific cases the calibration is required. Therefore, on a special request the following calibrations of standard as well as non-standard types of Hall probes can be provided:

  • up to ±0.1 T at room temperature
  • up to ±0.4 T at 77 K
  • up to ±5 T at 4.2 K

The linearity of the Hall probe is an expression of the extent to which the actual measured Hall voltage departs from the ideal linear curve. Figure 2 shows a somewhat exaggerated relationship between the ideal line and calibration line.

 

Calibration 3

List of symbols:
B - magnetic field
Uh - output voltage
K, Q - linear fit parameters
d - max. linearity error
U0 - residual voltage

 

Figure 2. Ideal versus measured curve showing the linearity error

 

With the calibrated Hall probe are supplied Uh(B) characteristics, data table, K and Q linear fit parameters and U0 residual voltage value. The magnetic field can be calculated:

Calibration 4

 

The maximum linearity error d can be defined according to the following expression:

Calibration 5

 

where DUh max is the maximum deviation from linear dependence of the Hall voltage
and Uh (B max) is maximum value of Uh at Bmax.


Polarity:

If the control current enters black current lead (connected to the positive terminal of the current supply) and the vector of induction enters the front part of the Hall probe, a positive Hall voltage will be generated at the orange lead.