ADR395 AD [Analog Devices], ADR395 Datasheet - Page 13

• Manufacturer Part Number: ADR395
• Description: Complete Dual, 16-Bit, High Accuracy, Serial Input, Bipolar Voltage Output DACs
• Manufacturer: AD [Analog Devices]

Preliminary Technical Data
TERMINOLOGY
Relative Accuracy or Integral nonlinearity (INL)
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 can be seen in Figure 7.
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. A
typical DNL vs. code plot can be seen in Figure 9.
Monotonicity
A DAC is monotonic if the output either increases or remains
constant for increasing digital input code. The AD5762R is
monotonic over its full operating temperature range.
Bipolar Zero Error
Bipolar zero error is the deviation of the analog output from the
ideal half-scale output of 0 V when the DAC register is loaded with
0x8000 (offset binary coding) or 0x0000 (twos complement
coding). A plot of bipolar zero error vs. temperature can be seen in
Figure 22.
Bipolar Zero TC
Bipolar zero TC is the measure of the change in the bipolar zero
error with a change in temperature. It is expressed in ppm FSR/°C.
Full-Scale Error
Full-scale error is a measure of the output error when full-scale
code is loaded to the DAC register. Ideally the output voltage
should be 2 × V
percentage of full-scale range.
Negative Full-Scale Error/Zero Scale Error
Negative full-scale error is the error in the DAC output voltage
when 0x0000 (offset binary coding) or 0x8000 (twos
complement coding) is loaded to the DAC register. Ideally, the
output voltage should be −2 × V
temperature can be seen in Figure 21.
Output Voltage Settling Time
Output voltage settling time is the amount of time it takes for
the output to settle to a specified level for a full-scale input
change.
Slew Rate
The slew rate of a device is a limitation in the rate of change of
the output voltage. The output slewing speed of a voltage-
output D/A converter is usually limited by the slew rate of the
amplifier used at its output. Slew rate is measured from 10% to
90% of the output signal and is given in V/µs.
REF
− 1 LSB. Full-scale error is expressed in
REF
. A plot of zero-scale error vs.
Rev. PrA | Page 13 of 33
Gain Error
Gain error is a measure of the span error of the DAC. It is the
deviation in slope of the DAC transfer characteristic from the
ideal, expressed as a percentage of the full-scale range. A plot of
gain error vs. temperature can be seen in Figure 23.
Total Unadjusted Error
Total unadjusted error (TUE) is a measure of the output error
considering all the various errors. A plot of total unadjusted
error vs. reference can be seen in Figure 19.
Zero-Scale Error TC
Zero-scale error TC is a measure of the change in zero-scale
error with a change in temperature. Zero-scale error TC is
expressed in ppm FSR/°C.
Gain Error TC
Gain error TC is a measure of the change in gain error with
changes in temperature. Gain Error TC is expressed in
(ppm of FSR)/°C.
Digital-to-Analog Glitch Energy
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 (0x7FFF to 0x8000) (see Figure 28).
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.
Power Supply Sensitivity
Power supply sensitivity indicates how the output of the DAC is
affected by changes in the power supply voltage.
DC Crosstalk
DC crosstalk is the dc change in the output level of one DAC in
response to a change in the output of another DAC. It is
measured with a full-scale output change on one DAC while
monitoring another DAC, and is expressed in LSBs.
DAC-to-DAC Crosstalk
DAC-to-DAC crosstalk is the glitch impulse transferred to the
output of one DAC due to a digital code change and subsequent
output change of another DAC. This includes both digital and
analog crosstalk. It is measured by loading one of the DACs
with a full-scale code change (all 0s to all 1s and vice versa) with
LDAC low and monitoring the output of another DAC. The
energy of the glitch is expressed in nV-s.
AD5762R