–3–
REV. B
AD7851
A Grade: fCLKIN = 7 MHz (–40 C to +85 C), fSAMPLE = 333 kHz; K Grade: fCLKIN = 6 MHz (0 C to 85 C), fSAMPLE = 285 kHz; A and K Grade: fCLKIN = 5 MHz
(to 125 C), fSAMPLE = 238 kHz; (AVDD = DVDD = 5.0 V
5%, REFIN/REFOUT = 4.096 V External Reference; SLEEP = Logic High; TA = TMIN to TMAX,
unless otherwise noted.)
Parameter
Version A
1
Version K
1
Unit
Test Conditions/Comments
DYNAMIC PERFORMANCE
Signal-to-Noise + Distortion Ratio
3 (SNR)
77
78
dB min
Typically SNR Is 79.5 dB.
VIN = 10 kHz, Sine Wave, fSAMPLE = 333 kHz.
Total Harmonic Distortion (THD)
–86
dB max
VIN = 10 kHz, Sine Wave, fSAMPLE = 333 kHz,
typically –96 dB.
Peak Harmonic or Spurious Noise
–87
dB max
VIN = 10 kHz, fSAMPLE = 333 kHz.
Intermodulation Distortion (IMD)
Second-Order Terms
–86
–90
dB typ
fa = 9.983 kHz, fb = 10.05 kHz, fSAMPLE = 333 kHz.
Third-Order Terms
–86
–90
dB typ
fa = 9.983 kHz, fb = 10.05 kHz, fSAMPLE = 333 kHz.
Full Power Bandwidth
20
MHz typ
@ 3 dB.
DC ACCURACY
Resolution
14
Bits
Integral Nonlinearity
±2
±1
LSB max
Differential Nonlinearity
±2
±1
LSB max
Guaranteed No Missed Codes to 14 Bits
Unipolar Offset Error
±10
LSB max
Review: Adjusting the Offset Calibration
Positive Full-Scale Error
±10
LSB max
Register in the Calibration Registers section.
Negative Full-Scale Error
±10
LSB typ
Bipolar Zero Error
±1
LSB typ
ANALOG INPUT
Input Voltage Ranges
0 V to VREF 0 V to VREF
V
AIN(+) – AIN(–) = 0 V to VREF, AIN(–) can be
biased up but AIN(+) cannot go below AIN(–).
±V
REF/2
±V
REF/2
V
AIN(+) – AIN(–) = –VREF/2 to +VREF/2, AIN(–)
should be biased up and AIN(+) can go below
AIN(–) but cannot go below 0 V.
Leakage Current
±1
A max
Input Capacitance
20
pF typ
REFERENCE INPUT/OUTPUT
REFIN Input Voltage Range
4/VDD
V min/max
Functional from 1.2 V.
Input Impedance
150
k
typ
Resistor Connected to Internal Reference Node.
REFOUT Output Voltage
3.696/4.496 3.696/4.496
V min/max
REFOUT Temperature Coefficient
50
ppm/
°C typ
LOGIC INPUTS
Input High Voltage, VINH
VDD – 1.0
V min
Input Low Voltage, VINL
0.4
V max
Input Current, IIN
±10
A max
VIN = 0 V or VDD.
Input Capacitance, CIN
4
10
pF max
LOGIC OUTPUTS
Output High Voltage, VOH
VDD – 0.4
V min
ISOURCE = 200
A.
Output Low Voltage, VOL
0.4
V max
ISINK = 0.8 mA.
Floating State Leakage Current
±10
A max
Floating State Output Capacitance
4
10
pF max
Output Coding
Straight (Natural) Binary
Unipolar Input Range.
Twos Complement
Bipolar Input Range.
CONVERSION RATE
Conversion Time
2.78
3.25
s max
19.5 CLKIN Cycles.
Conversion + Track-and-Hold
Acquisition Time
3.0
3.5
s max
21 CLKIN Cycles Throughput Rate.
SPECIFICATIONS1, 2