AD668 AD [Analog Devices], AD668 Datasheet - Page 4

• Manufacturer Part Number: AD668
• Description: 12-Bit Ultrahigh Speed Multiplying D/A Converter
• Manufacturer: AD [Analog Devices]

AD668
DEFINITIONS
LINEARITY ERROR (also called INTEGRAL NONLINEAR-
ITY OR INL): Analog Devices defines linearity error as the
maximum deviation of the actual analog output from the ideal
output (a straight line drawn from 0 to FS) for any bit combina-
tion expressed in multiples of 1 LSB. The AD668 is laser
trimmed to 1/4 LSB (0.006% of FS) maximum linearity error at
+25 C for the K version and 1/2 LSB for the J and S versions.
DIFFERENTIAL LINEARITY ERROR (also called DIFFER-
ENTIAL NONLINEARITY or DNL): DNL is the measure of
the variation in the analog output, normalized to fun scale, asso-
ciated with a 1 LSB change in digital input code.
MONOTONICITY: A DAC is said to be monotonic if the out-
put either increases or remains constant as the digital input in-
creases. Monotonic behavior requires that the differential
linearity error not exceed 1 LSB in the negative direction.
UNIPOLAR OFFSET ERROR (DAC OFFSET): The DAC
offset is the portion of the DAC output that is independent of
the digital input. The unipolar DAC offset error is measured as
the deviation of the analog output from the ideal (0 V or 0 mA)
when the analog input is set to 100% and the digital inputs are
set to all 0s.
Model
AD668JQ
AD668KQ
AD668SQ
NOTES
1
2
AD668AQ
Analog Devices Military Products Databook or current AD668/883B data sheet.
For details on grade and package offerings screened in accordance with MIL-STD-883, refer to the
Q = Cerdip.
1
–40 C to +85 C
–55 C to +125 C
Temperature
Range
0 C to +70 C
0 C to +70 C
PIN CONFIGURATION
ORDERING GUIDE
Linearity
Error Max
@ 25 C
1/2
1/4
1/2
1/2
–4–
BIPOLAR OFFSET ERROR: The deviation of the analog out-
put from the ideal (negative half-scale) when the DAC is con-
nected in the bipolar mode (Pin 16 connected to Pin 20), the
analog input is set to 100%, and the digital inputs are set to all
0s is called the bipolar offset error.
BIPOLAR ZERO ERROR: The deviation of the analog output
from the ideal (0 V or 0 mA) for bipolar mode when only the
MSB is on (100 . . . 00) is called bipolar zero error.
COMPLIANCE VOLTAGE: The allowable voltage excursion
at the output node of a DAC which will not degrade the accu-
racy of the DAC output.
SETTLING TIME (DIGITAL CHANNEL): The time re-
quired for the output to reach and remain within a specified
error band about its final value, measured from the digital input
transition.
SETTLING TIME (ANALOG CHANNEL): The time re-
quired for the output to reach and remain within a specified er-
ror band about its final value, measured from the analog input’s
crossing of it’s 50% value.
GAIN ERROR: The difference between the ideal and actual
output span of FS – 1 LSB, expressed either in % of FS or LSB,
when all bits are on is called the gain error.
Gain T.C.
Max ppm/ C
Voltage
30
15
30
40
Package
Option
Q-24
Q-24
Q-24
Q-24
2
REV. A