Advantech USB-5820, User Manual

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21 USB-5820 User Manual
Chapter 3
S
ignal Connections
Figure 3.4 Voltage output generation
The USB-5820 is equipped with four 16-bit digital-to-analog converters (DACs),
which means that the output voltage can be generated from one of 65,536 (216)
codes. Take ±10 V output range as an example, the voltage resolution can be calcu-
lated as
Due to offset and gain correction, the resolution may vary, but only for a small quan-
tity which can be neglected.
3.5.2 Current Input Measurement
The USB-5820 supports the following current output ranges: 0 ~ 20 mA and 4 ~ 20
mA. The current is sourced from the AO pin and return to the ground pin. Therefore,
the load should be connected between each AO pin and the ground pin. This is
shown in Figure 3.5.
Figure 3.5 Current output generation
The USB-5820 is equipped with four 16-bit digital-to-analog converters (DACs),
which means that the output current can be generated from one of 65,536 (216)
codes. Take 0 ~ 20 mA output range as an example, the current resolution can be
calculated as
Due to offset and gain correction, the resolution may vary, but only for a small quan-
tity which can be neglected.