ADLINK Technology NuDAQ ACL-8216, Руководство пользователя

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Calibration & Utilities
VR2 A/D full scale adjustment
VR3 D/A channel 1 full scale adjustment
VR4 D/A channel 2 full scale adjustment
VR5 A/D programmable amplifier offset adjustment
VR6 D/A reference voltage adjustment
Table 6.1 Function of VRs
6.3 A/D Adjustment
1. Set the analog input range as: +/- 10V, i.e. the gain = 1
2. Short the A/D channel 0 ( pin 1 of CN3) to ground(GND), and
connect the TP1(+) and TP2(-) with your DVM. Trim the variable
resister VR5 to obtain a value as close as possible to 0V. ( You have
to keep reading for A/D channel 0).
3. Applied a +10V input signal to A/D channel 1, and short the A/D
CH0 to Analog ground( A.GND).
4. Trim VR1 until the reading of CH0 between 0000 ~ 0001(hex).
5. Trim VR2 until the reading of CH1 between 7FFE ~ 7FFF(hex).
6. Repeat step 4 and step 5, adjust until the reading values meet
requirements.
Note: When the user trims the VR1 and VR2, it will have side effect on
the D/A converted data, so repeat the step 4 and step 5 are very
important issue for A/D calibration.
6.4 D/A Adjustment
There are two steps to calibrate the analog output channels, D/A 1
and D/A 2. The first step is to adjust the reference voltage, a nd the
second step is to adjust each channel of D/A.
6.4.1 Reference Voltage Calibration
1. Set reference voltage as -5V ( the D/A reference voltage is selected
by JP1, see section 2.11).