ADLINK PCI-9524 - Manual (Page 90)

74 Calibration
PCI-9524 ADLINK Technology Inc.
User’s Manual Copyright 2008
5.2 Auto-calibration
By using the auto-calibration feature of PCI-9524, the calibration
software can measure and minimize measurement errors without
external signal connections, reference voltages, or measurement
devices.
PCI-9524 has an on-board calibration reference to ensure the
accuracy of auto-calibration. The reference voltage is measured
on the production line through a digital potentiometer and compen-
sated in the software. The calibration constant is memorized after
this measurement.
5.3 Saving Calibration Constants
Factory calibrated constants are permanently stored in a onboard
EEPROM data bank and cannot be modified. When you re-cali-
brate the device, software stores new constants in a user-modifi-
able section of the EEPROM. To return a device to its initial factory
calibration settings, software copies the factory calibrated con-
stants to the user-modifiable section of the EEPROM. After an
auto-calibration is completed, users can save the new calibration
constants into the user-modifiable banks in the EEPROM. The
date, temperature and calibration constants of the auto-calibration
will be saved. Therefore users can store three sets of calibration
constants according to three different environments and re-load
the calibration constants later.
NOTE: NOTE:
1) Before auto-calibration starts, it is recommended to warm up
the card for at least 25 minutes.
2) Please remove cables before an auto-calibration procedure
is initiated because the DA outputs will change in the calibra-
tion process.