AD625
40
30
+V
S
INPUT CURRENT – nA
20
10
0
–10
–20
–30
–V
S
V
OUT
10V
AD625
–40
–125
–75
–25
25
75
TEMPERATURE – C
125
Figure 10. Input Bias Current vs.
Temperature
Figure 11. Overrange and Gain
Switching Test Circuit (G = 8, G = 1)
Figure 12. Gain Overrange Recovery
CURRENT NOISE SPECTRAL DENSITY – fA/ Hz
8.0
100k
AMPLIFIER QUIESCENT CURRENT – A
1000
VOLT NSD – nV/ Hz
6.0
10k
100
G=1
G = 10
4.0
1k
10
G = 100, 1000
G = 1000
2.0
100
1
0
0
5
10
15
SUPPLY VOLTAGE – V
20
0.1
1
10
100
1k
FREQUENCY – Hz
10k
100k
10
1
10
100
1k
FREQUENCY – Hz
10k
100k
Figure 13. Quiescent Current vs.
Supply Voltage
Figure 14. RTI Noise Spectral
Density vs. Gain
Figure 15. Input Current Noise
+V
S
–V
S
AD625
DUT
+V
S
1 F
1/2
AD712
9.09k
G = 1, 10, 100
G = 1000
100
1k
–V
S
1.62M
1.82k
1/2
1 F
16.2k
AD712
16.2k
1 F
Figure 16. Low Frequency Voltage
Noise, G = 1 (System Gain = 1000)
Figure 17. Noise Test Circuit
Figure 18. Low Frequency Voltage
Noise, G = 1000 (System
Gain = 100,000)
–6–
REV. D
AD [ ANALOG DEVICES ]
