Corporation Computer Hardware User Manual

Prometheus CPU User Manual V1.44 Page 55
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