Hercules-EBX CPU User Manual V1.02
Page 89
D/A Conversion Formulas for Bipolar Output Ranges
Output voltage = ((D/A code – 2048) / 2048) * Output reference
D/A code = (Output voltage / Output reference) * 2048 + 2048
Example: Output range in bipolar mode =
±
10V
Full-scale range = 10V – (-10V) = 20V
Desired output voltage = 2.000V
D/A code = 2V / 10V * 2048 + 2048 = 2457.6 => 2458
For the bipolar output range
±
10V, 1 LSB = 1/4096 * 20V, or 4.88mV.
Here is an illustration of the relationship between D/A code and output voltage for a bipolar output
range (V
REF
= Reference voltage):
D/A Code
Output voltage symbolic formula
Output voltage for
±
10V range
0
-V
REF
-10.0000V
1
-V
REF
+ 1 LSB
-9.9951V
…
…
…
2047
-1
LSB
-0.0049V
2048
0
0.0000V
2049
+1
LSB
0.0049V
…
…
…
4095
V
REF
- 1 LSB
9.9951V