Data Translation DT330 Series, Getting Started Manual

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Using Your Own Screw Terminal Panel
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Analog Outputs
The analog output channels on DT330 Series boards have a resolution
of 12 or 16 bits (even though the accuracy may be less).
Data Translation ensures that the analog outputs do not break into a
high frequency oscillation with high capacitance loads that may be
experienced with long cables. Typically, the analog outputs drive
1,000 pF without degradation and bandwidth-limit with higher
capacitive loads.
The grounds of most boards are optimized for analog inputs at the
expense of some logic or high-frequency noise on the analog outputs.
This is because the analog and digital grounds of the board are
connected at the ADC’s input.
The analog outputs are brought out as a high and a low signal, but
the low side is the analog ground at the DAC’s output buffer. To
remove the high-frequency noise and smooth the glitch energy on the
analog outputs, you can install a 15 kHz RC filter on the output, a
100
Ω
resistor in series with the output, and a 0.1
µ
F capacitor
between the output side of the 100
Ω
resistor and output low.