AD7705/AD7706
Rev. C | Page 5 of 44
SPECIFICATIONS
V
DD
= 3 V or 5 V, REF IN(+) = 1.225 V with V
DD
= 3 V, and 2.5 V with V
DD
= 5 V; REF IN(−) = GND; MCLK IN = 2.4576 MHz, unless
otherwise noted. All specifications T
MIN
to T
MAX
, unless otherwise noted.
Table 1.
Parameter B Version
1
Unit Conditions/Comments
STATIC PERFORMANCE
No Missing Codes 16 Bits min Guaranteed by design, filter notch < 60 Hz
Output Noise
See
Table 5 and
Table 7
Depends on filter cutoffs and selected gain
Integral Nonlinearity
2
±0.003 % of FSR max Filter notch < 60 Hz, typically ±0.0003%
Unipolar Offset Error
3
Unipolar Offset Drift
4
0.5 μV/°C typ
Bipolar Zero Error
3
Bipolar Zero Drift
4
0.5 μV/°C typ For gains 1, 2, and 4
0.1 μV/°C typ For gains 8, 16, 32, 64, and 128
Positive Full-Scale Error
3, 5
Full-Scale Drift
4, 6
0.5 μV/°C typ
Gain Error
3, 7
Gain Drift
4, 8
0.5
ppm of FSR/°C
typ
Bipolar Negative Full-Scale Error
2
±0.003 % of FSR typ Typically ±0.001%
Bipolar Negative Full-Scale Drift
4
1 μV/°C typ For gains of 1 to 4
0.6 μV/°C typ For gains of 8 to 128
ANALOG INPUTS/REFERENCE INPUTS
Specifications for AIN and REF IN, unless otherwise
noted
Common-Mode Rejection (CMR)
2
V
DD
= 5 V
Gain = 1 96 dB typ
Gain = 2 105 dB typ
Gain = 4 110 dB typ
Gain = 8 to 128 130 dB typ
V
DD
= 3 V
Gain = 1 105 dB typ
Gain = 2 110 dB typ
Gain = 4 120 dB typ
Gain = 8 to 128 130 dB typ
Normal-Mode 50 Hz Rejection
2
98 dB typ For filter notches of 25 Hz, 50 Hz, ±0.02 × f
NOTCH
Normal-Mode 60 Hz Rejection
2
98 dB typ For filter notches of 20 Hz, 60 Hz, ±0.02 × f
NOTCH
Common-Mode 50 Hz Rejection
2
150 dB typ For filter notches of 25 Hz, 50 Hz, ±0.02 × f
NOTCH
Common-Mode 60 Hz Rejection
2
150 dB typ For filter notches of 20 Hz, 60 Hz, ±0.02 × f
NOTCH
Absolute/Common-Mode REF IN
Voltage
2
GND to V
DD
V min to V max
Absolute/Common-Mode AIN
Voltage
2, 9, 10
GND − 100 mV V min BUF bit of setup register = 0
V
DD
+ 30 mV V max
Absolute/Common-Mode AIN
Voltage
2, 9
GND + 50 mV V min BUF bit of setup register = 1
V
DD
− 1.5 V V max
AIN DC Input Current
2
1 nA max
AIN Sampling Capacitance
2
10 pF max
AIN Differential Voltage Range
11
0 to +V
REF
/gain
12
nom
Unipolar input range (B
/U bit of setup register = 1)
±V
REF
/gain nom
Bipolar input range (B
/U bit of setup register = 0)