Datasheet

AD5061
Rev. B | Page 14 of 20
TERMINOLOGY
Relative Accuracy
For the DAC, relative accuracy or integral nonlinearity (INL) is
a measure of the maximum deviation, in LSBs, from a straight
line passing through the endpoints of the DAC transfer
function. A typical INL vs. code plot is shown in Figure 4.
Differential Nonlinearity (DNL)
Differential nonlinearity is the difference between the measured
change and the ideal 1 LSB change between any two adjacent codes.
A specified differential nonlinearity of ±1 LSB maximum ensures
monotonicity. This DAC is guaranteed monotonic by design. A
typical AD5061 DNL vs. code plot is shown in Figure 6.
Zero-Code Error
Zero-code error is a measure of the output error when zero
code (0x0000) is loaded to the DAC register. Ideally, the output
should be 0 V. The zero-code error is always positive in the
AD5061 because the output of the DAC cannot go below 0 V.
This is due to a combination of the offset errors in the DAC and
output amplifier. Zero-code error is expressed in mV.
Full-Scale Error
Full-scale error is a measure of the output error when full-scale
code (0xFFFF) is loaded to the DAC register. Ideally, the output
should be V
DD
− 1 LSB. Full-scale error is expressed in percent
of full-scale range.
Gain Error
This is a measure of the span error of the DAC. It is the devia-
tion in slope of the DAC transfer characteristic from ideal
expressed as a percent of the full-scale range.
Total Unadjuste d Error ( T UE)
Total unadjusted error is a measure of the output error taking
all the various errors into account. A typical TUE vs. code plot
is shown in Figure 5.
Zero-Code Error Drift
This is a measure of the change in zero-code error with a
change in temperature. It is expressed in μV/°C.
Gain Error Drift
This is a measure of the change in gain error with changes in
temperature. It is expressed in (ppm of full-scale range)/°C.
Digital-to-Analog Glitch Impulse
Digital-to-analog glitch impulse is the impulse injected into the
analog output when the input code in the DAC register changes
state. It is normally specified as the area of the glitch in nV-s
and is measured when the digital input code is changed by
1 LSB at the major carry transition; see Figure 17 and Figure 21.
The expanded view in Figure 17 shows the glitch generated
following completion of the calibration routine; Figure 21
zooms in on this glitch.
Digital Feedthrough
Digital feedthrough is a measure of the impulse injected into
the analog output of the DAC from the digital inputs of the
DAC, but is measured when the DAC output is not updated. It
is specified in nV-s and measured with a full-scale code change
on the data bus; that is, from all 0s to all 1s, and vice versa.