DATA SHEET
HAL 710, HAL 730
5. Application Notes
5.3. Signal Delay
5.1. Ambient Temperature
The extra circuitry required for the direction detection
increases the latency of the Count and Direction Sig-
nal compared to a simple switch (e.g., HAL 525). This
extra delay corresponds to 0.5 and 1 clock period for
the Direction Signal and Count Signal respectively.
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).
5.4. Test Mode Activation
TJ = TA + ΔT
In order to obtain the normal operation as described
above, two external pull-up resistors with appropriate
values are required to connect each output to an exter-
nal supply, such that the potential at the open-drain
output rises to at least 3 V in less than 10 µs after hav-
ing turned off the corresponding pull-down transistor or
At static conditions and continuous operation, the fol-
lowing equation applies:
after having applied VDD
.
ΔT = IDD × VDD × Rth
If the Direction Output is pulled low externally (the
potential does not rise after the internal pull-down tran-
sistor has been turned off), the device enters Manufac-
turer Test Mode.
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 appli-
cation.
Direction detection is not functional in Manufacturer
Test Mode. The device returns to normal operation as
soon as the Count Output goes high.
For all sensors, the junction temperature range TJ is
specified. The maximum ambient temperature TAmax
can be calculated as:
Note: The presence of a Manufacturer Test Mode
requires appropriate measures to prevent acci-
dental activation (e.g., in response to EMC
events).
TAmax = TJmax – ΔT
5.2. Extended Operating Conditions
All sensors fulfill the electrical and magnetic character-
istics when operated within the Recommended Oper-
ating Conditions (see Section 3.5. 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.
Note: The functionality of the sensor below 3.8 V is
not tested. For special test conditions, please
contact Micronas.
Micronas
Oct. 13, 2009; DSH000031_002EN
17
MICRONAS [ MICRONAS ]
