HAL1000
DATA SHEET
2.3. General Calibration Procedure
Note: The magnetic south pole on the branded side
generates negative ADC-READOUT values, the
north polarity positive values.
For calibration in the system environment, the applica-
tion kit from Micronas is recommended. It contains the
hardware for the generation of the serial telegram for
programming and the corresponding software for the
input or calculating of the register values.
Then, set the system to the calibration point where the
sensor output must be low, press the key “Readout
B
” and get the second ADC-READOUT value.
In this section, the programming of the sensor using
this tool is explained. Please refer to Section 5. on
page 23 for information about programming without
this tool.
ON
Now, adjust the hysteresis to the desired value. The
hysteresis is the difference between the switching
points and suppresses oscillation of the output signal.
With 100% hysteresis, the sensor will switch low and
high exactly at the calibration points. A lower value will
adjust the switching points closer together. Fig. 2–9
shows an example with 80% hysteresis.
For the individual calibration of each sensor in the cus-
tomer‘s application, a two-point adjustment is recom-
mended (see Fig. 2–9 for an example). When using
the application kit, the calibration can be done in three
steps:
By pressing the key “calibrate and store”, the software
will calculate the corresponding parameters for Sensi-
tivity, VOQ, Low-Level, High-Level and store these val-
ues in the EEPROM.
Step 1: Input of the registers which need not be
adjusted individually
This calibration must be done individually for each
sensor.
The magnetic circuit, the magnetic material with its
temperature characteristics, and the filter frequency,
are given for this application.
The sensor is now calibrated for the customer applica-
tion. However, the programming can be changed
again and again if necessary.
Therefore, the values of the following registers should
be identical for all sensors in the application.
– FILTER
(according to the maximum signal frequency)
The 500 Hz range is recommended for highest
accuracy.
V
OUT
Hysteresis
– RANGE
Sensor
Sensor
switched off
switched on
(according to the maximum magnetic field at the
sensor position)
(here 80 %)
– TC and TCSQ
(depends on the material of the magnet and the
other temperature dependencies of the application)
position
Calibration points
Write the appropriate settings into the HAL1000 regis-
ters.
Fig. 2–9: Characteristics of a position switch
Step 3: Locking the Sensor
Step 2: Calculation of the Sensor Parameters
The last step is activating the LOCK function with the
“lock” key. The sensor is now locked and does not
respond to any programming or reading commands.
Fig. 2–9 shows the typical characteristics for a contact-
less switch. There is a mechanical range where the
sensor must be switched high and where the sensor
must be switched low.
Warning: The LOCKR register cannot be reset!
Set the system to the calibration point where the sen-
sor output must be high, and press the key “Readout
B
”. The result is the corresponding ADC-READ-
OFF
OUT value.
10
March 4, 2004; 6251-528-1DS
Micronas
MICRONAS [ MICRONAS ]
