600
400
200
400
300
200
100
MEAN
± 2 SIGMA
MEAN
± 2 SIGMA
0
-200
-400
0
-100
-600
-200
4.4
4.6
4.8
5.0
5.2
5.4
5.6
4.4
4.6
4.8
5.0
5.2
5.4
5.6
V
– INPUT SUPPLY VOLTAGE – V
V
– OUTPUT SUPPLY VOLTAGE – V
DD1
DD2
Figure 3. Input-Referred Offset Drift
vs. VDD1 (VDD2 = 5 V).
Figure 4. Input-Referred Offset Drift
vs. VDD2 (VDD1 = 5 V).
1.5
1.0
0.5
MEAN
± 2 SIGMA
+5 V
+5 V
+15 V
0.1 µF
0.1 µF
HCPL-7800
0.1 µF
10 K
8
7
1
2
3
4
V
+
IN
V
OUT
0
-0.5
-1.0
6
5
AD624CD
GAIN = 1
-
10 K
0.01 µF
0.1 µF
0.33 µF
0.33 µF
-40
-20
0
20
40
60
80
100
-15 V
T
– TEMPERATURE – °C
A
Figure 5. Gain and Nonlinearity Test Circuit.
Figure 6. Gain Drift vs. Temperature.
0.3
0.5
0
0.5
0.4
0.3
MEAN
± 2 SIGMA
MEAN
± 2 SIGMA
0.2
0.1
-0.5
-1.0
0
0.2
0.1
-0.1
-1.5
-0.2
-0.3
0
MEAN
± 2 SIGMA
-0.1
-2.0
-0.2
-0.1
0
0.1
0.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
4.4
4.6
4.8
5.0
5.2
5.4
5.6
V
– INPUT VOLTAGE – V
V
– INPUT SUPPLY VOLTAGE – V
V
– OUTPUT SUPPLY VOLTAGE – V
DD1
IN
DD2
Figure 7. Gain Drift vs.
VDD1 (VDD2 = 5 V).
Figure 8. Gain Drift vs.
VDD2 (VDD1 = 5 V).
Figure 9. 200 mV Nonlinearity Error
Plot.
1-225
HP [ HEWLETT-PACKARD ]
