Chapter 8 Tutorial

Multifunction Module

DAC Errors

The output of a DAC varies with temperature. If possible, you should operate the instrument at a stable temperature and as close as possible to the calibration temperature of the DAC for greater accuracy.

The output of a DAC also exhibits two other types of errors: differential error and integral error.

Differential Error refers to the smallest possible change in voltage. The DAC output is not linear, but is stepped as progressively larger (or smaller) voltages are programmed. The step size is 1 mV.

Integral Error refers to the difference between the programmed voltage and the actual output voltage from the DAC. This error is included in the output specifications shown on page 412.

Differential Error

Integral Error

Vout

Vprogrammed

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