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Vout vref dan = − × 4096, 2 d/a conversion – ADLINK ACL-8111 User Manual

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30

Operation Theorem

4.2 D/A

Conversion

The operation of D/A conversion is simpler than A/D operation. You only
need to write digital values into the D/A data registers and the corresponding
voltage will be output from the AO. The ACL-8111 has one uni-polar analog
output channels. To make the D/A output connections from the appropriate
D/A output, please refer Figure 4.2.

To D/A Output

D/A Converter

-

+

Ref In

-5 or -10

INT or Ext

Analog GND

Pin-30 ( AO)

Pin-20 ( A.GND)

Figure 4.2 Connection of Analog Output Connection

The mathematical relationship between the digital number DAn and the
output voltage is formulated as following:

Vout

Vref

DAn

= −

×

4096

Where the Vref is the reference voltage, the Vout is the output voltage, and
the DAn is the digital value in D/A data registers.
Before performing the D/A conversion, users should care about the D/A
reference voltage, which set by the JP1. Please refer section 2.6 for jumper
setting. The reference voltage will effect the output voltage. If the reference
voltage is -5V, the D/A output scaling will be 0~5V. If the reference voltage is
-10V, the D/A output scaling will be 0~10V. The relationship of reference
voltage and output range is summary in the following table.

Reference Voltage

DA Output Voltage Range

-5 V

0V ~ +5V

-10 V

0V ~ +10V