Datasheet

11
®
INA118
FIGURE 9. ECG Amplifier With Right-Leg Drive.
FIGURE 8. Differential Voltage to Current Converter.
A
1
I
B
Error
OPA177 ±1.5nA
OPA602 ±1pA
OPA128 ±75fA
FIGURE 5. Single-Supply Bridge Amplifier.
FIGURE 6. AC-Coupled Instrumentation Amplifier.
SEEBECK
ISA COEFFICIENT
TYPE MATERIAL (
µV/°C) R
1
, R
2
E + Chromel 58.5 66.5kΩ
– Constantan
J + Iron 50.2 76.8kΩ
– Constantan
K + Chromel 39.4 97.6kΩ
– Alumel
T + Copper 38.0 102kΩ
– Constantan
FIGURE 7. Thermocouple Amplifier With Cold Junction
Compensation.
300Ω
+3V
150Ω
R
1
(1)
2V – ∆V
2V + ∆V
NOTE: (1) R
1
required to create proper common-mode voltage,
onl
y
for low volta
g
e operation — see text.
3V
R
G
INA118
V
O
Ref
INA118
R
G
V
O
C
1
0.1µF
OPA602
Ref
R
1
1MΩ
f
–3dB
=
1
2πR
1
C
1
= 1.59Hz
V
IN
+
–
REF102
R
2
R
1
R
3
Pt100
Cu
Cu
V+
K
6
10.0V
4
2
INA118
V
O
Ref
100Ω = RTD at 0°C
R
G
INA118
R
G
I
B
R
1
V
IN
–
+
A
1
I
O
Load
I
O
= • G
V
IN
R
1
Ref
INA118
R
G
/2
V
O
LA
RL
RA
10kΩ
Ref
G = 102.8kΩ
2.8kΩ
1/2
OPA2604
390kΩ
390kΩ
1/2
OPA2604