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2.1 Analog Output
The IP-OPTODA16CH4 includes 4 channels of analog outputs with a resolution of 16 bits and a voltage
range of +/-10V or 0V to +10V. The maximum output current for each channel is +/-4mA. Each channel
has a settling time to 0.003%of typical 10
µ
s.
Two voltage ranges are jumper selectable: +/-10V or 0V to +10V. Voltage range selection covers all 4
channels.
The 4 analog outputs of the IP-OPTODA16CH4 are galvanically isolated from the IndustryPack logic
interface by optocoupler.
2.2 Data Correction
There are two errors which affect the DC accuracy of the DAC. The first is the zero error (offset). For the
DAC this is the data value required to produce a zero voltage output signal. This error is corrected by
subtracting the known error from all readings.
The second error is the gain error. Gain error is the difference between the ideal gain and the actual gain
of the DAC. It is corrected by multiplying the data value by a correction factor.
The data correction values are obtained during factory calibration and are stored in the modules individual
version of the ID PROM. The DAC has a pair of offset and gain correction values for each single output
channel. The correction values are stored in the ID PROM as two’s complement byte wide values in the
range -32768 to 32767. For higher accuracy they are scaled to ¼ LSB.
Because offset and gain correction values are dependent on the selected output voltage range the IP-
OPTODA16CH4 has 2 different sets of ID PROM data. Depending on the jumper settings for the voltage
range the corresponding set of correction values is automatically selected.
2.2.1 DAC Correction Formula for 0V to +10V Output Voltage Range
The basic formula for correcting unipolar DAC output value is:
Data = Value * ( 1 - Gain
corr
/ 262144 ) - Offset
corr
/ 4
Data is the (corrected) digital value that should be sent to the DAC, Value is the desired output value,
Gain
corr
and Offset
corr
are the correction factors from the ID PROM.
