DATA SHEET
HAL82x
4. Application Notes
V
DD
4.1. Application Circuit
OUT A & Select A
OUT B & Select B
For EMC protection, it is recommended to connect one
ceramic 4.7 nF capacitor each between ground and
the supply voltage, respectively the output voltage pin.
In addition, the input of the controller unit should be
pulled-down with a 10 kΩ resistor and a ceramic
4.7 nF capacitor.
HAL82x
Sensor A
HAL82x
Sensor B
10 nF
4.7 nF
4.7 nF
GND
Please note that during programming, the sensor will
be supplied repeatedly with the programming voltage
of 12.5 V for 100 ms. All components connected to the
VDD line at this time must be able to resist this voltage.
Fig. 4–2: Parallel operation of two HAL82x
4.3. Temperature Compensation
V
DD
The relationship between the temperature coefficient
of the magnet and the corresponding TC, TCSQ and
TC-Range codes for linear compensation is given in
the following table. In addition to the linear change of
the magnetic field with temperature, the curvature can
be adjusted as well. For this purpose, other TC, TCSQ
and TC-Range combinations are required which are
not shown in the table. Please contact Micronas for
more detailed information on this higher order temper-
ature compensation.
OUT
HAL82x
μC
4.7 nF
4.7 nF
4.7 nF
10 kΩ
GND
Fig. 4–1: Recommended application circuit
Temperature
TC-Range TC
TCSQ
Coefficient of
Magnet (ppm/K)
4.2. Use of two HAL82x in Parallel
Two different HAL82x sensors which are operated in
parallel to the same supply and ground line can be
programmed individually. In order to select the IC
which should be programmed, both Hall ICs are inacti-
vated by the “Deactivate” command on the common
supply line. Then, the appropriate IC is activated by an
“Activate” pulse on its output. Only the activated sen-
sor will react to all following read, write, and program
commands. If the second IC has to be programmed,
the “Deactivate” command is sent again, and the sec-
ond IC can be selected.
1075
1000
900
750
675
575
450
400
250
150
50
3
3
3
3
3
3
3
1
1
1
1
1
1
1
1
1
31
28
24
16
12
8
7
1
0
2
2
2
2
0
1
1
2
1
0
1
4
7
4
31
24
20
16
15
12
8
Note: The multi-programming of two sensors works
only if the outputs of the two sensors are pulled
to GND with a 10 kΩ pull-down resistor.
0
−100
−200
−300
−400
4
0
Micronas
Feb. 3, 2009; DSH000143_003EN
23
MICRONAS [ MICRONAS ]
