HAL810 Datasheet, PDF (12/30 Pages) Micronas – Programmable Linear Hall-Effect Sensor

HAL 810
DATA SHEET
Step 1: Input of the registers which need not be
adjusted individually
The register values for the following registers are given
for all applications:
– FILTER
Select the filter frequency: 500 Hz
– RANGE
Select the magnetic field range: 30 mT
– TC
For this magnetic material: 6
– TCSQ
For this magnetic material: 14
– Min-Duty
For our example: 5%
– Max-Duty
For our example: 95%
Enter these values in the software, and use the “write
and store” command for permanently writing the val-
ues in the registers.
Step 2: Calculation of DC_OQ and DCSensitivity
There are two ways to calculate the values for DC_OQ
and DCSensitivity.
Manual Calculation:
Set the system to calibration point 1 (angle 1 = −25°)
and read the register ADC-READOUT. For our exam-
ple, the result is ADC-Readout1 = −2500.
Next, set the system to calibration point 2
(angle 2 = 25°), and read the register ADC-READOUT
again. For our example, the result is
ADC-Readout2 = +2350.
With these measurements and the targets DC₁ = 95%
and DC₂ = 5%, the values for DCSensitivity and DC_OQ
are calculated as follows
5% − 95%
2048
DCSensitivity = _{2350 + 2500 * 100%} = −0.3800
DC_OQ = 95% −
−2500*(−0.3800)*100%
2048
= 48.61%
Software Calibration:
Use the menu CALIBRATE from the PC software and
enter the values 95% for DC₁ and 5% for DC₂. Set the
system to calibration point 1 (angle 1 = −25°), press
the key “Read ADC-Readout1”, set the system to cali-
bration point 2 (angle 2 = 25°), press the key
“Read ADC-Readout2”, and hit the button “Calculate”.
The software will then calculate the appropriate DC_OQ
and DCSensitivity.
This calculation has to be done individually for each
sensor. Now, write the calculated values with the “write
and store” command into the HAL810 for program-
ming the sensor.
Step 3: Locking the Sensor
The last step is to activate the lock function with the
“lock” command. Please note that the LOCK function
becomes effective after power-down and power-up of
the Hall IC. The sensor is now locked and does not
respond to any programming or reading commands.
Warning: This register cannot be reset!
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Feb. 6, 2009; DSH000034_003EN
Micronas