HAL810 Datasheet, PDF (10/30 Pages) Micronas – Programmable Linear Hall-Effect Sensor

HAL 810
DATA SHEET
Clamping Function
The output duty cycle range can be clamped in order
to detect failures like shorts of the output signal to V_DD
or GND or an open circuit.
The MIN-DUTY register contains the parameter for the
lower limit. The minimum duty cycle is programmable
between 0% and 50% in steps of 0.0488%.
The MAX-DUTY register contains the parameter for
the upper limit. The maximum duty cycle is program-
mable between 0% and 100% in steps of 0.0488%.
LOCKR
By setting this 1-bit register, all registers will be locked,
and the sensor will no longer respond to any supply
voltage modulation. This bit is active after the first
power-off and power-on sequence after setting the
LOCK bit.
Warning: This register cannot be reset!
ADC-READOUT
This 14-bit register delivers the actual digital value of
the applied magnetic field before the signal process-
ing. This register can be read out and is the basis for
the calibration procedure of the sensor in the system
environment.
2.3. Calibration Procedure
2.3.1. General Procedure
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 of the register values.
In this section, programming of the sensor using this
programming tool is explained. Please refer to
Section 5. on page 25 for information about program-
ming without this tool.
For the individual calibration of each sensor in the cus-
tomer application, a two-point adjustment is recom-
mended (see Fig. 2–7 for an example). When using
the application kit, the calibration can be done in three
steps:
Step 1: Input of the registers which need not be
adjusted individually
The magnetic circuit, the magnetic material with its
temperature characteristics, the filter frequency, and
low and high clamping duty cycles are given for this
application.
Therefore, the values of the following registers should
be identical for all sensors of the customer application.
– Filter
(according to the maximum signal frequency)
– Range
(according to the maximum magnetic field at the
sensor position)
– TC and TCSQ
(depends on the material of the magnet and the
other temperature dependencies of the application)
– Min-Duty and Max-Duty
(according to the application requirements)
Write and store the appropriate settings into the
HAL810 registers.
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Feb. 6, 2009; DSH000034_003EN
Micronas