ZSSC3026 Datasheet, PDF (41/51 Pages) List of Unclassifed Manufacturers – Low Power, High Resolution 16-Bit Sensor Signal Conditioner

ZSSC3026
Within this minimum 3x3 measurements field, data must be collected for the specific value pairs at known
conditions and then processed to calculate the coefficients. In order to obtain the potentially best and most robust
coefficients, it is recommended that measurement pairs (temperature vs. measurand) be collected at the outer
corners of the intended operation range or at least at points that are located far from each other. It is also
essential to provide highly precise reference values as nominal, expected values. The measurement precision of
the external calibration-measurement equipment should be ten times more accurate than the expected
ZSSC3026 output precision after calibration in order to avoid precision losses caused by the nominal reference
values (e.g., measurand signal and temperature deviations).
Note: An appropriate selection of measurement pairs can significantly improve the overall system performance.
The determination of the measurand-related coefficients will use all of the measurement pairs. For the
temperature-related correction coefficients, 3 (at three different temperatures) of the measurement pairs will be
used.
Note: There is an inherent redundancy in the 7 bridge-related and 3 temperature-related coefficients. Since the
temperature is a necessary output (which also needs correction), the temperature-related information is mathe-
matically separated, which supports faster and more efficient DSP calculations during the normal usage of the
sensor-ZSSC3026 system.
The recommended approach for data collection is to make use of the raw-measurement commands:
• For bridge sensor values:
o A2_HEX + 0000_HEX: Single bridge measurement for which the configuration register will be loaded
from the BM_config register (10_HEX in MTP); preprogramming the measure-
ment setup in the MTP is required.
o A3_HEX + ssss_HEX: Single bridge measurement for which the BM_config configuration register
(Gain, ADC, Offset, etc.) will be loaded as ssss_HEX and must be provided
externally via the interface.
• For temperature values:
o A6_HEX + 0000_HEX: Single temperature measurement for which the configuration register will be
loaded from an internal temperature configuration register (preprogrammed by
IDT in MTP); preprogramming of the respective configuration is done by IDT
prior to ZSSC3026 delivery. This is the recommended approach for
temperature data collection.
o A7_HEX + ssss_HEX: Single temperature measurement for which the configuration register (Gain,
ADC, Offset, etc.) will be loaded as ssss_HEX and must be provided externally
via the interface. The data composition of the temperature configuration
register is similar to the BM_config (address 10_HEX) register for the bridge
sensor.
3.7.3. Calibration Step 3 – Coefficient Calculations
The math to perform the coefficient calculation is complicated and will not be discussed in detail. There is a brief
overview in the next section. IDT will provide software (DLLs) to perform the coefficient calculation (external to the
sensor-ZSSC3026 system) based on auto-zero corrected values. After the coefficients are calculated, the final
step is to write them to the MTP memory of the ZSSC3026.
© 2016 Integrated Device Technology, Inc.
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March 28, 2016