Z-World Wolf BL2600, Руководство пользователя

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26 Wolf (BL2600)
3.5 D/A Converter Outputs
The four D/A converter outputs are buffered and scaled to provide an output from 0 V to
+10 V (12-bit resolution) or ±10 V (11-bit resolution, one bit used for polarity). There are
also four 4–20 mA current outputs. Figure 17 shows the D/A converter outputs.
Figure 17. D/A Converter Outputs
To stay within the maximum power dissipation of the D/A converter circuit, the maximum
D/A converter output current is 10 mA per channel for the voltage outputs. If you are
using the current outputs, keep the resistance driven by a current output channel below
400
Ω
to stay within the power dissipation capabilities of the D/A converter circuit.
As Figure 17 shows, both the voltage and the current outputs for a particular channel are
driven by the same output on the D/A converter chip. As a result, either the
anaOutVolts
or the
anaOutmAmps
function calls will set both the voltage and the current outputs corre-
sponding to a particular channel. For example, if
anaOutVolts
sets unipolar channel
AV0 to be +10 V, AI0 will be 20 mA; if
anaOutVolts
sets unipolar channel AV0 to be
+5 V, AI0 will be 12 mA, the midpoint of the 4–20 mA range. It is possible to connect a
load to both the corresponding voltage and current outputs as long as the combined current
consumption does not exceed the 20 mA individual limit.
Because of the “connection” between the analog voltage outputs and the analog current
outputs, the configuration of the analog voltage outputs with the
anaOutConfig
function
call as unipolar outputs with 12-bit resolution or as bipolar outputs with 11-bit resolution
52.3 k W
DAC
10 k W
AV0
AGND
1.667 V ref.
11 k W
AV1
2.5 V ref.
1.33 k W
1.33 k W
11 k W
11 k W
AI0
AI1