Table of Contents
Advertisement
Calibration
_______
Outline.
The calibration is simple. It consists of only two steps.
i)
Set the D/A converter to its LOWEST output, then using
an accurate voltmeter check the output voltage, adjust the
OFFSET trim potentiometer to get the desired value.
ii)
Set the D/A converter to its HIGHEST output, then using
an accurate voltmeter check the output voltage, adjust the
GAIN trim potentiometer to get the desired value.
Provided the calibration is performed in the correct order,
OFFSET adjust then GAIN adjust, there should be no interaction
between the two adjustments.
__________________ _
Equipment Required.
A digital voltmeter capable of a stable and clear resolution
of 1/10th of LSB at both ends of the range of the converter.
Thus the voltmeter should have a range of -10 to +10 volts and
a resolution of 1.22mV/10 = 122uV or better.
_________________________________ _
Figure 4-1. DAC Trimmer Pot Layout.
DAC1
UNIOFFSET
BPOFFSET
GAIN
POT9
POT7
POT8
Chapter 4
DAC0
UNIOFFSET
BPOFFSET
GAIN
POT6
POT4
POT5
AD1200 Reference
Page 73
Advertisement
Table of Contents
