AD5697R datasheet(15/27 Pages) AD

15 / 27 page

Data Sheet

AD5697R

Rev. B | Page 15 of 27

TERMINOLOGY

Relative Accuracy or Integral Nonlinearity (INL)

For the DAC, relative accuracy or integral nonlinearity is a

measurement 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 11.

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 DNL vs. code plot can be seen in Figure 12.

Zero-Code Error

Zero-code error is a measurement 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 AD5697R because the output of the DAC cannot go less than

0 V due to a combination of the offset errors in the DAC and the

output amplifier. Zero-code error is expressed in mV. A plot of

the zero-code error vs. the temperature can be seen in Figure 17.

Full-Scale Error

Full-scale error is a measurement of the output error when the

full-scale code is loaded to the DAC register. Ideally, the output

should be VDD − 1 LSB. Full-scale error is expressed in percent of

full-scale range (% of FSR). A plot of the full-scale error vs. the

temperature can be seen in Figure 16.

Gain Error

This 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 % of FSR.

Offset Error Drift

This is a measurement of the change in offset error with a change

in temperature. It is expressed in µV/°C.

Gain Temperature Coefficient

This is a measurement of the change in gain error with changes

in temperature. It is expressed in ppm of FSR/°C.

Offset Error

Offset error is a measure of the difference between VOUT (actual)

and VOUT (ideal) expressed in mV in the linear region of the

transfer function. Offset error is measured on the AD5697R with

Code 512 loaded in the DAC register. It can be negative or positive.

DC Power Supply Rejection Ratio (PSRR)

This indicates how the output of the DAC is affected by changes

in the supply voltage. PSRR is the ratio of the change in VOUT to

a change in VDD for full-scale output of the DAC. It is measured

in mV/V. VREF is held at 2 V, and VDD is varied by ±10%.

Output Voltage Settling Time

Output voltage settling time is the time it takes for the output of a

DAC to settle to a specified level for a ¼ to ¾ full-scale input

change.

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-sec

and is measured when the digital input code is changed by 1 LSB at

the major carry transition, 0x7FFF to 0x8000 (see Figure 32).

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-sec, and measured with a full-scale code change on the

data bus, that is, from all 0s to all 1s and vice versa.

Reference Feedthrough

Reference feedthrough is the ratio of the amplitude of the signal

at the DAC output to the reference input when the DAC output

is not being updated. It is expressed in dB.

Noise Spectral Density

This is a measurement of the internally generated random noise.

Random noise is characterized as a spectral density (nV/√Hz).

It is measured by loading the DAC to midscale and measuring

noise at the output. It is measured in nV/√Hz. A plot of noise

spectral density is shown in Figure 36.

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 (or soft power-down

and power-up) while monitoring another DAC kept at midscale.

It is expressed in μV.

DC crosstalk due to load current change is a measure of the impact

that a change in load current on one DAC has to another DAC

kept at midscale. It is expressed in μV/mA.

Digital Crosstalk

This is the glitch impulse transferred to the output of one DAC

at midscale in response to a full-scale code change (all 0s to all

1s and vice versa) in the input register of another DAC. It is

measured in standalone mode and is expressed in nV-sec.

Analog Crosstalk

This is the glitch impulse transferred to the output of one DAC

due to a change in the output of another DAC. It is measured by

loading one of the input registers with a full-scale code change

(all 0s to all 1s and vice versa). Then execute a software LDAC

and monitor the output of the DAC whose digital code was not

changed. The area of the glitch is expressed in nV-sec.

AD5697R Datasheet(PDF) 15 Page - Analog Devices

AD5697R Datasheet(HTML) 15 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Datasheet Download

Link URL