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DM35425HR User’s Manual
7.3
DAC Calibration
The DAC circuit requires gain calibration. TR11-TR14 adjust the DAC gain. The table below provides, for your reference, a list of the input bits
and their corresponding ideal output voltages for each of the three output ranges.
Table 29: DAC Bit Weights
DAC Bit Weight
Ideal Output Voltages (mV)
-5 to +5 V 0 to +5 V -10 to +10 V 0 to +10 V
1111 1111 1111
+4997.56 +4998.78
+9995.12
+9997.56
1000 0000 0000
0 +2500.00
0000.00
+5000.00
0100 0000 0000
-2500.00 +1250.00
-5000.00
+2500.00
0010 0000 0000
-3750.00
+625.00
-7500.00
+1250.00
0001 0000 0000
-4375.00
+312.50
-8750.00
+625.00
0000 1000 0000
-4687.50
+156.25
-9375.00
+312.50
0000 0100 0000
-4843.75
+78.13
-9687.50
+156.25
0000 0010 0000
-4921.88
+39.06
-9843.75
+78.13
0000 0001 0000
-4960.94
+19.53
-9921.88
+39.06
0000 0000 1000
-4980.47
+9.77
-9960.94
+19.53
0000 0000 0100
-4990.24
+4.88
-9980.47
+9.77
0000 0000 0010
-4995.12
+2.44
-9990.23
+4.88
0000 0000 0001
-4997.56
+1.22
-9995.12
+2.44
0000 0000 0000
-5000.00
0.00
-10000.00
0.00
Table 30: Trimpots for Calibrating DAC Gain
DAC
Trimpot
AOUT0
TR11
AOUT1
TR12
AOUT2
TR13
AOUT3
TR14