–2–
AD7568–SPECIFICATIONS
1
Parameter AD7568B
2
Units Test Conditions/Comments
ACCURACY
Resolution 12 Bits 1 LSB = V
REF
/2
12
= 1.22 mV when V
REF
= 5 V
Relative Accuracy ±0.5 LSB max
Differential Nonlinearity ±0.9 LSB max All Grades Guaranteed Monotonic over Temperature
Gain Error
+25°C ±4 LSBs max
T
MIN
to T
MAX
±5 LSBs max
Gain Temperature Coefficient 2 ppm FSR/°C typ
5 ppm FSR/°C max
Output Leakage Current
I
OUT1
@ +25°C 10 nA max See Terminology Section
T
MIN
to T
MAX
200 nA max
REFERENCE INPUT
Input Resistance 5 kΩ min Typical Input Resistance = 7 kΩ
9kΩ max
Ladder Resistance Mismatch 2 % max Typically 0.6%
DIGITAL INPUTS
V
INH
, Input High Voltage 2.4 V min
V
INL
, Input Low Voltage 0.8 V max
I
INH
, Input Current ±1 µA max
C
IN
, Input Capacitance 10 pF max
POWER REQUIREMENTS
V
DD
Range 4.75/5.25 V min/V max
Power Supply Sensitivity
∆Gain/∆V
DD
–75 dB typ
I
DD
300 µA max V
INH
= 4.0 V min, V
INL
= 0.4 V max
3.5 mA max V
INH
= 2.4 V min, V
INL
= 0.8 V max
AC PERFORMANCE CHARACTERISTICS
Parameter AD7568B
2
Units Test Conditions/Comments
DYNAMIC PERFORMANCE
Output Voltage Settling Time 500 ns typ To 0.01% of Full-Scale Range. DAC Latch Alternately
Loaded with All 0s and All 1s.
Digital to Analog Glitch Impulse 40 nV–s typ Measured with V
REF
= 0 V. DAC Register Alternately
Loaded with All 0s and All 1s.
Multiplying Feedthrough Error –66 dB max V
REF
= 20 V pk-pk, 10 kHz Sine Wave. DAC Latch
Loaded with All 0s.
Output Capacitance 60 pF max All 1s Loaded to DAC.
30 pF max All 0s Loaded to DAC.
Channel-to-Channel Isolation –76 dB typ Feedthrough from Any One Reference to the Others
with 20 V pk-pk, 10 kHz Sine Wave Applied.
Digital Crosstalk 40 nV–s typ Effect of all 0s to all 1s Code Transition on
Nonselected DACs.
Digital Feedthrough 40 nV–s typ Feedthrough to Any DAC Output with
FSIN High
and Square Wave Applied to SDIN and SCLK.
Total Harmonic Distortion –83 dB typ V
REF
= 6 V rms, 1 kHz Sine Wave.
Output Noise Spectral Density
@ 1 kHz 20 nV/√
Hz All 1s Loaded to the DAC. V
REF
= 0 V. Output Op
Amp is AD OP07.
NOTES
1
Temperature range as follows: B Version: –40°C to +85°C.
2
All specifications also apply for V
REF
= +10 V, except relative accuracy which degrades to ±1 LSB.
Specifications subject to change without notice.
(V
DD
= +4.75 V to +5.25 V; I
OUT1
= I
OUT2
= O V; V
REF
= +5 V; T
A
= T
MIN
to T
MAX
,
unless otherwise noted)
(These characteristics are included for Design Guidance and are not subject
to test. DAC output op amp is AD843.)
