Vr Assignment; A/D Adjustment - NuDAQ PCI- 9113A User Manual

7.1.1

VR Assignment

There are four variable resistors (VR) on the PCI-9113A board to allow
you making accurate adjustment on A/D channels. The function of each
VR is specified as Table 7.1.
VR1
VR2
VR3
VR4
7.1.2

A/D Adjustment

7.1.2.1
1. Set JP5 as single-ended input
2. Short the A/D channel 0 (pin 1 of CN1) to ground (GND: pin 9 of CN1).
3. Use multi -meter to measure the voltage between TP1 and TP2.
4. Adjust VR4 until the multi-meter value approach to zero.
7.1.2.2
1. Set JP5 as single-ended input
2. Set JP2 as uni-polar A/D input.
3. Set JP3 to 10V full range.
4. Set JP4 to direct binary coding.
5. Short the A/D channel 0 (pin 1 of CN1) to ground (GND: pin 9 of CN1).
6. Set the analog gain = 1 and channel num ber #0 by software.
7. Adjust VR1 to obtain reading between 0~1.
8. Applied a +10V reference input signal to A/D channel 0, and trim the
VR2 to obtain reading between 4094~4095.
7.1.2.3
1. Set JP5 as single-ended input
2. Set JP2 as bi-polar A/D input.
3. Set JP3 to 20V full range.
4. Set JP4 to direct binary coding.
70 Calibration and Utilities
A/D uni-polar offset adjustment
A/D full scale adjustment
A/D bi-polar offset adjustment
PGA offset adjustment
Table 7.1 Function of VRs
PGA offset calibration
Uni-polar input
Bi-polar input