Datasheet

AD8221
Rev. C | Page 11 of 24
0.40
0.45
0.50
0.55
0.60
0.65
INPUT BIAS CURRENT (nA)
0.70
0.75
0.80
–5 0–15 –10 5 10 15
COMMON-MODE VOLTAGE (V)
03149-009
V
S
= ±5V
V
S
= ±15V
Figure 10. I
BIAS
vs. CMV
0
0.25
0.50
0.75
1.00
1.25
CHANGE IN INPUT OFFSET VOLTAGE (µV)
1.50
1.75
2.00
0.10.01 1 10
WARM-UP TIME (min)
03149-010
Figure 11. Change in Input Offset Voltage vs. Warm-Up Time
–5
–4
–3
–2
–1
0
1
2
3
4
5
INPUT CURRENT (nA)
–40 –20 0 20 40 60 80 100 120 140
TEMPERATURE (°C)
03149-011
INPUT BIAS CURRENT
VS = ±15V
INPUT OFFSET CURRENT
Figure 12. Input Bias Current and Offset Current vs. Temperature
20
40
60
80
100
120
POSITIVE PSRR (dB)
140
160
180
0.1 1 10 100 1k 10k 100k 1M
FREQUENCY (Hz)
03149-012
GAIN = 1
GAIN = 10
GAIN = 100
GAIN = 1000
GAIN = 1000
Figure 13. Positive PSRR vs. Frequency, RTI (G = 1 to 1000)
20
40
60
80
100
120
NEGATIVE PSRR (dB)
140
160
180
0.1 1 10 100 1k 10k 100k 1M
FREQUENCY (Hz)
03149-013
GAIN = 1
GAIN = 10
GAIN = 100
GAIN = 1000
Figure 14. Negative PSRR vs. Frequency, RTI (G = 1 to 1000)
TOTAL DRIFT 25°C – 85°C RTI (µV)
10
100
1k
10k
100k
1k 10k10 100 100k 1M 10M
SOURCE RESISTANCE (Ω)
03149-014
BEST AVAILABLE FET
INPUT IN-AMP GAIN = 1
BEST AVAILABLE FET
INPUT IN-AMP GAIN = 1000
AD8221 GAIN = 1
AD8221 GAIN = 1000
Figure 15. Total Drift vs. Source Resistance