Specification Definitions

DIFFERENTIAL NON-LINEARITY (DNL) is the measure of

the maximum deviation from the ideal step size of 1 LSB,

which is V

DAC-to-DAC CROSSTALK is the glitch impulse transferred

to a DAC output in response to a full-scale change in the

output of another DAC.

DIGITAL CROSSTALK is the glitch impulse transferred to a

DAC output at mid-scale in response to a full-scale change

in the input register of another DAC.

DIGITAL FEEDTHROUGH is a measure of the energy in-

jected into the analog output of the DAC from the digital

inputs when the DAC outputs are not updated. It is mea-

sured with a full-scale code change on the data bus.

FULL-SCALE ERROR is the difference between the actual

output voltage with a full scale code (3FFh) loaded into the

DAC and the value of V

GAIN ERROR is the deviation from the ideal slope of the

transfer function. It can be calculated from Zero and Full-

Scale Errors as GE = FSE - ZE, where GE is Gain error, FSE

is Full-Scale Error and ZE is Zero Error.

GLITCH IMPULSE is the energy injected into the analog

output when the input code to the DAC register changes. It is

specified as the area of the glitch in nanovolt-seconds.

INTEGRAL NON-LINEARITY (INL) is a measure of the

deviation of each individual code from a straight line through

the input to output transfer function. The deviation of any

given code from this straight line is measured from the

center of that code value. The end point method is used. INL

for this product is specified over a limited range, per the

Electrical Tables.

LEAST SIGNIFICANT BIT (LSB) is the bit that has the

smallest value or weight of all bits in a word. This value is

LSB=V

n

where V

the DAC resolution in bits, which is 10 for the DAC102S085.

MAXIMUM LOAD CAPACITANCE is the maximum capaci-

tance that can be driven by the DAC with output stability

maintained.

MONOTONICITY is the condition of being monotonic, where

the DAC has an output that never decreases when the input

code increases.

MOST SIGNIFICANT BIT (MSB) is the bit that has the

largest value or weight of all bits in a word. Its value is 1/2 of

V

MULTIPLYING BANDWIDTH is the frequency at which the

output amplitude falls 3dB below the input sine wave on

V

POWER EFFICIENCY is the ratio of the output current to the

total supply current. The output current comes from the

power supply. The difference between the supply and output

currents is the power consumed by the device without a

load.

SETTLING TIME is the time for the output to settle to within

1/2 LSB of the final value after the input code is updated.

TOTAL HARMONIC DISTORTION (THD) is the measure of

the harmonics present at the output of the DACs with an

ideal sine wave applied to V

WAKE-UP TIME is the time for the output to exit power-

down mode. This is the time from the falling edge of the 16th

SCLK pulse to when the output voltage deviates from the

power-down voltage of 0V.

ZERO CODE ERROR is the output error, or voltage, present

at the DAC output after a code of 000h has been entered.

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