Omega Engineering DAQ-12 - Manual (Page 15)

The D/A converter channels may also be operated in unipolar mode: 0 to +5 volts, or bipolar
mode: -5 to +5 volts. The output mode is selected using jumper J5 as shown in Figure 2-5. In
addition, a gain selection jumper is provided to select an output gain of 1 or 2. When using
an external voltage reference, this gain can be used to amplify the D/A output for small
reference voltages.
WARNING: When the internal voltage reference is used,the D/A gain MUST be set to the
gain = 1 position.
5 6 7 8
1 2 3 4
J5
Channel 1 gain
Channel 1 select
Channel 0 select
Channel 0 gain
Figure 2-5. Jumper J5 Configuration
Table 2-3 lists configuration options for jumper J5.
connect 4-8
open 4-8 connect 2-6
open 2-6 Gain = 1
Gain = 2
connect 3-7
open 3-7 connect 1-5
open 1-5 Bipolar
Unipolar
Channel 1 Channel 0
Table 2-3. D/A Converter Mode Selection Options
When configured for unipolar operation, the output voltage can be calculated from the
equation:
A = V * * gain
out ref
CODE
4096
For bipolar operation, the equation becomes:
A = - 1 * V * gain
out
CODE
2048 ref
DAQ-12 Users Manual 15