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Chapter 5      Analog Output Reference
Measure Data Acquisition User Manual
5-4
© National Instruments Corporation
Table 5-2. Advanced Analog Output Configuration Options
Option
Description
High Limit (volts)
The high limit is equal to your reference voltage and is the maximum
voltage the DAC can produce. If you have an AT-AO-6/10 board and
your Channel Type is current, you can calculate the maximum possible
current with the following equation.
Imax = Vref + 2.5/0.625  mA
The following list contains the default settings for high limit. If you
want to use a high limit that differs from the ones given in this list, you
must supply an external voltage reference on the 
EXTREF
 pin of the
connector and select the External Voltage Reference option.
Most devices:          10.0 V
Lab/1200 Series:  -5.0 V or 10.0 V
Low Limit (volts)
The low limit is either 0.0 Volts or a value equal to, but opposite in
sign, to the upper limit.
External Voltage
Reference
Select this option if you want to supply an external voltage reference
on the 
EXTREF
 pin of the connector.