ADLINK PXI-2208 - Manual (Page 97)

Calibration 85
5 Calibration
This chapter introduces the calibration process to minimize AD
measurement errors and DA output errors.
5.1 Loading Calibration Constants
The DAQ-/DAQe-/PXI-2204/2205/2206/2208 card is factory-cali-
brated before shipment. The associated calibration constants of
the TrimDACs firmware to the onboard EEPROM. TrimDACs are
devices containing multiple DACs within a single package. Trim-
DACs do not have memory capability. That means the calibration
constants do not retain their values after the system power is
turned off. Loading calibration constants is the process of loading
the values of TrimDACs firmware stored in the onboard EEPROM.
ADLINK provides a software utility that automatically reads the
calibration constants automatically, if necessary.
There is a dedicated space for storing calibration constants in the
EEPROM. In addition to the default bank of factory calibration con-
stants, there is one user-utilization bank. This bank allows you to
load the TrimDACs firmware values either from the original factory
calibration or from a subsequently-performed calibration.
Because of the fact that measurements and outputs errors may
vary depending on time and temperature, it is recommended that
you calibrate the card when it is integrated in your computing envi-
ronment. The auto-calibration function is presented in the follow-
ing sections.