6.2VR Assignment
There are five variable resistors (VR) on the
VR1 | D/A full scale adjustment |
VR2 | D/A offset adjustment |
VR3 | A/D offset adjustment |
VR4 | A/D full scale adjustment |
VR5 | A/D programmable amplifier offset adjustment |
| Table 6.1 Functions of VRs |
6.3A/D Adjustment
1.Set the analog gain = 1 and channel number #0 by software.
2.Short the A/D channel 0 (pin 1 of CN3) to ground (GND), and connect the TP1(+) and
3.Applied a +10V reference input signal to A/D channel 0, and trim the VR4 to obtain reading between 2046~2047(9111DG) or 32766~32767(9111HR).
4.Short the A/D channel 0 to ground, and trim the VR3 to obtain reading flickers between 0~1.
5.Repeat step 3 and step 4, adjust VR4 and VR3.
66 ∙ Calibration