HAL525 Datasheet, PDF (23/24 Pages) List of Unclassifed Manufacturers – Hall Effect Sensor IC

DATA SHEET
HAL 525, HAL 526
5. Application Notes
5.1. Ambient Temperature
Due to the internal power dissipation, the temperature
on the silicon chip (junction temperature T_J) is higher
than the temperature outside the package (ambient
temperature T_A).
T_J = T_A + ΔT
At static conditions and continuous operation, the fol-
lowing equation applies:
ΔT = I_DD × V_DD × R_th
If I_OUT > I_DD, please contact Micronas application sup-
port for detailed instructions on calculating ambient-
temperature.
For typical values, use the typical parameters. For
worst case calculation, use the max. parameters for
I_DD and R_th, and the max. value for V_DD from the appli-
cation.
For all sensors, the junction temperature range T_J is
specified. The maximum ambient temperature T_Amax
can be calculated as:
T_Amax = T_Jmax – ΔT
5.2. Extended Operating Conditions
All sensors fulfill the electrical and magnetic character-
istics when operated within the Recommended Oper-
ating Conditions (see page 13).
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.
5.3. Start-Up Behavior
Due to the active offset compensation, the sensors
have an initialization time (enable time t_en(O)) after
applying the supply voltage. The parameter t_en(O) is
specified in the Characteristics (see page 14).
During the initialization time, the output state is not
defined and the output can toggle. After t_en(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 B_OFF.
For magnetic fields between B_OFF and B_ON, the output
state of the HAL sensor after applying V_DD will be
either low or high. In order to achieve a well-defined
output state, the applied magnetic field must be above
B_ONmax, respectively, below B_OFFmin.
5.4. EMC and ESD
For applications with disturbances on the supply line or
radiated disturbances, a series resistor and a capacitor
are recommended (see Fig. 5–1). The series resistor
and the capacitor should be placed as closely as pos-
sible to the HAL sensor.
Applications with this arrangement passed the EMC
tests according to the product standards ISO 7637.
Please contact Micronas for the detailed investigation
reports with the EMC and ESD results.
R_V
220 Ω
V_EMC
V_P
1 V_DD
4.7 nF
2 GND
OUT
3
R_L 1.2 kΩ
20 pF
Fig. 5–1: Test circuit for EMC investigations
Note: The functionality of the sensor below 3.8 V is
not tested. For special test conditions, please
contact Micronas.
Micronas
Nov. 30, 2009; DSH000144_003EN
23