AD5757 Analog Devices, AD5757 Datasheet - Page 22

• Manufacturer Part Number: AD5757
• Description: Quad Channel, 16-Bit, Serial Input, 4-20mA Output DAC, Dynamic Power Control, HART Connectivity
• Manufacturer: Analog Devices

Specifications of AD5757

• Resolution (bits): 16bit
• Dac Update Rate: 60kSPS
• Dac Settling Time: 15µs
• Max Pos Supply (v): +33V
• Single-supply: No
• Dac Type: Current Out
• Dac Input Format: SPI

AD5757
TERMINOLOGY
Relative Accuracy or Integral Nonlinearity (INL)
For the DAC, relative accuracy, or integral nonlinearity, is a
measure of the maximum deviation, in LSBs, from the best fit
line through the DAC transfer function. A typical INL vs. code
plot is shown in Figure 8.
Differential Nonlinearity (DNL)
Differential nonlinearity (DNL) 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 DNL vs. code plot is shown in
Figure 9.
Monotonicity
A DAC is monotonic if the output either increases or remains
constant for increasing digital input code. The AD5757 is
monotonic over its full operating temperature range.
Offset Error
Offset error is the deviation of the analog output from the ideal
zero-scale output when all DAC registers are loaded with
0x0000.
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 the ideal,
expressed in % FSR.
Gain TC
This is a measure of the change in gain error with changes in
temperature. Gain TC 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 should be
full-scale − 1 LSB. Full-scale error is expressed in percent of
full-scale range (% FSR).
Full-Scale TC
Full-scale TC is a measure of the change in full-scale error with
changes in temperature and is expressed in ppm FSR/°C.
Total Unadjusted Error
Total unadjusted error (TUE) is a measure of the output error
taking all the various errors into account, including INL error,
offset error, gain error, temperature, and time. TUE is expressed
in % FSR.
DC Crosstalk
This 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, which is at midscale.
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Current Loop Compliance Voltage
The maximum voltage at the I
current is equal to the programmed value.
Voltage Reference Thermal Hysteresis
Voltage reference thermal hysteresis is the difference in output
voltage measured at +25°C compared to the output voltage
measured at +25°C after cycling the temperature from +25°C to
−40°C to +105°C and back to +25°C. The hysteresis is specified
for the first and second temperature cycles and is expressed in ppm.
Power-On Glitch Energy
Power-on glitch energy is the impulse injected into the analog
output when the AD5757 is powered-on. It is specified as the area
of the glitch in nV-sec. See Figure 24.
Power Supply Rejection Ratio (PSRR)
PSRR indicates how the output of the DAC is affected by
changes in the power supply voltage.
Reference TC
Reference TC is a measure of the change in the reference output
voltage with a change in temperature. It is expressed in ppm/°C.
Line Regulation
Line regulation is the change in reference output voltage due to
a specified change in supply voltage. It is expressed in ppm/V.
Load Regulation
Load regulation is the change in reference output voltage due to
a specified change in load current. It is expressed in ppm/mA.
DC-to-DC Converter Headroom
This is the difference between the voltage required at the
current output and the voltage supplied by the dc-to-dc
converter. See Figure 31.
Output Efficiency
This is defined as the power delivered to a channel’s load vs. the
power delivered to the channel’s dc-to-dc input.
Efficiency at V
This is defined as the power delivered to a channel’s V
supply vs. the power delivered to the channel’s dc-to-dc input.
The V
dc converter’s losses.
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