Gain for DSA Devices

On DSA devices, each gain setting corresponds to a particular range centered on 0 V. The gain settings are specified in decibels (dB), where the 0 dB reference is the default range of ±10 V.

For analog input operations, a negative gain value implies attenuation of the signal before the ADC, increasing the range beyond ±10 V. Thus, an input gain setting of –10 dB corresponds to an input range of ±31.6 V. On analog output, a negative gain value implies attenuation following the DAC. This decreases the output range. For instance, an output gain setting of –20 dB corresponds to an output range of ±1 V.

NI-DAQmx has three separate attribute/property sets you can use to control the hardware gain setting. Each has a different priority. If you write values to two or more of these attributes/properties that correspond to different hardware gain settings, the one with the highest priority will determine the hardware behavior.