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53
DM35425HR User’s Manual
7
Calibration
This section describes how to calibrate the DM35425HR using the trimpots on the module. The trimpots calibrate the A/D converter gain and
offset.
The D/A converter does not need to be calibrated. The offset and full-
scale performance of the module’s A/D converter is factory
- calibrated.
Any time you suspect inaccurate readings, you can check the accuracy of your conversions using the procedure in this section, and make
adjustments as necessary.
Calibration is done with the module installed in your system. Power up the system and let the DM35425HR circuitry stabilize for 15 minutes
before calibration.
7.1
Required Equipment
The following equipment is required for calibration:
Precision voltage source: -10 to +10 V
Digital voltmeter: 5 ½ digits
Small screwdriver (for trimpot adjustment)
The figure below shows the DM35425HR layout with the trimpots located along the top.
Figure 10: DM35425HR Trimpots
TR9
TR13
TR14
TR2
TR3
TR8
TR5
TR6
TR4
TR7
TR11
TR12