Datasheet

AD8231
Rev. B | Page 5 of 24
V
S
= 3.0 V, V
REF
= 1.5 V, T
A
= 25°C, G = 1, R
L
= 10 kΩ, unless otherwise noted.
Table 3.
Parameter Conditions Min Typ Max Unit
INSTRUMENTATION AMPLIFIER
Offset Voltage V
OS
RTI = V
OSI
+ V
OSO
/G
Input Offset, V
OSI
4 15 μV
Average Temperature Drift 0.01 0.05 μV/°C
Output Offset, V
OSO
15 30 μV
Average Temperature Drift 0.05 0.5 μV/°C
Input Currents
Input Bias Current 250 500 pA
T
A
= −40°C to +125°C 5 nA
Input Offset Current 20 100 pA
T
A
= −40°C to +125°C 0.5 nA
Gains 1, 2, 4, 8, 16, 32, 64, or 128
Gain Error
G = 1 0.05 %
G = 2 to 128 0.8 %
Gain Drift T
A
= −40°C to +125°C
G = 1 to 32 3 10 ppm/°C
G = 64 4 20 ppm/°C
G = 128 10 30 ppm/°C
CMRR
G = 1 80 dB
G = 2 86 dB
G = 4 92 dB
G = 8 98 dB
G = 16 104 dB
G = 32 110 dB
G = 64 110 dB
G = 128 110 dB
Noise
e
n
= √(e
ni
2
+ (e
no
/G)
2
)
V
IN+
, V
IN−
= 2.5 V, T
A
= 25°C
Input Voltage Noise, e
ni
f = 1 kHz 40 nV/√Hz
f = 1 kHz, T
A
= −40°C 35 nV/√Hz
f = 1 kHz, T
A
= 125°C 48 nV/√Hz
f = 0.1 Hz to 10 Hz 0.8 μV p-p
Output Voltage Noise, e
no
f = 1 kHz 72 nV/√Hz
f = 1 kHz, T
A
= −40°C 62 nV/√Hz
f = 1 kHz, T
A
= 125°C 83 nV/√Hz
f = 0.1 Hz to 10 Hz 1.4 μV p-p
Current Noise f = 10 Hz 20 fA/√Hz
Other Input Characteristics
Common-Mode Input Impedance 10||5 GΩ||pF
Power Supply Rejection Ratio 100 115 dB
Input Operating Voltage Range 0.05 2.95 V
Reference Input
Input Impedance 28 kΩ||pF
Voltage Range −0.2 +3.2 V