DATA SHEET
HAL 2xy
4. Application Notes
4.2.2. Start-up Behavior
4.1. Ambient Temperature
Due to the active offset compensation, the sensors
have an initialization time (enable time ten(O)) after
applying the supply voltage. The parameter ten(O) is
specified in Section 3.6.: Characteristics on page 10.
Due to the internal power dissipation, the temperature
on the silicon chip (junction temperature TJ) is higher
than the temperature outside the package (ambient
temperature TA).
During the initialization time, the output state is not
defined and the output can toggle. After ten(O), the out-
put will be low if the applied magnetic field B is above
B
ON. The output will be high if B is below BOFF. In case
TJ = TA + ΔT
of sensors with an inverted switching behavior
(HAL211), the output state will be high if B > BOFF and
low if B < BON
.
At static conditions and continuous operation, the fol-
lowing equation applies:
For magnetic fields between BOFF and BON, the output
state of the HAL sensor after applying VDD will be
either low or high. In order to achieve a well-defined
output state, the applied magnetic field must be above
ΔT = IDD × VDD × Rth
B
ONmax, respectively, below BOFFmin.
4.3. HAL22y Operation
If IOUT > IDD, please contact Micronas application sup-
port for detailed instructions on calculating ambient
temperature.
4.3.1. Extended Operating Conditions
All sensors fulfill the electrical and magnetic character-
istics when operated within the Recommended Oper-
ating Conditions (see page 10).
For typical values, use the typical parameters. For
worst case calculation, use the max. parameters for
IDD and Rth, and the max. value for VDD from the
application.
Supply Voltage Below 4.3 V
For all sensors, the junction temperature range TJ is
specified. The maximum ambient temperature TAmax
can be calculated as:
The devices contain a Power-on Reset (POR) and a
undervoltage reset. For VDD < Vreset the output state is
high. For Vreset < VDD < 4.3 V the device responds to
the magnetic field according to the specified magnetic
characteristics.
TAmax = TJmax – ΔT
Note: The functionality of the sensor below 4.3 V is not
tested. For special test conditions, please con-
tact Micronas.
4.2. HAL20y, HAL21y Operation
4.2.1. Extended Operating Conditions
All sensors fulfill the electrical and magnetic character-
istics when operated within the Recommended Oper-
ating Conditions (see page 10).
4.3.2. Start-up Behavior
Due to the active offset compensation, the sensors
have an initialization time (enable time ten(O)) after
applying the supply voltage. The parameter ten(O) is
specified in Section 3.6.: Characteristics on page 10.
Supply Voltage Below 3.8 V
Typically, the sensors operate with supply voltages
above 3 V, however, below 3.8 V some characteristics
may be outside the specification.
During the initialization time, the output state for the
HAL22y is ‘Off-state‘ (i.e. Output High). After ten(O), the
output will high. The output will be switched to low if
the magnetic field B is above BON
.
Note: The functionality of the sensor below 3.8 V is
not tested. For special test conditions, please
contact Micronas.
Micronas
Jan. 11, 2010; DSH000141_003EN
15
MICRONAS [ MICRONAS ]
