+15V
+15V
V
Optional
Offset Adjust
100kΩ
15
4
12
+In
1
x1000
R
R
16
Shield
e2
5
Resistance
Bridge
e1
11
INA102
6
R
R
∆eIN
7
10
e1
14
eOUT = 1000 (e2 – e1)
–In
9
–15V
INA102 replaces classical three-op-amp
instrumentation amplifier.
FIGURE 5. Amplification of a Differential Voltage from a Resistance Bridge.
+15V
15
3
12
+In
Noise
(60Hz Hum)
x100
Shield
RG
11
7
INA102
Transducer
or
Analog
Signal
eOUT
6
10
14
–In
9
Transformer
Noise
(60Hz Hum)
–15V
eOUT = G (∆eIN
G = 1 + (40k/[RG + RY])
RG = (40k – RY[G – 1])/(G – 1)
)
R
Y ≈ 4.4kΩ, 404Ω, or 40Ω in gains
Note: Gain drift will be higher than that
specified with internal resistors only.
of 10, 100, or 1000 respectively.
FIGURE 6. Amplification of a Transformer-Coupled Analog Signal Using External Gain Set.
K
+15VDC
Thermocouple
15
3
+15VDC
–15VDC
12
+In
+15VDC
Digital
ISO
Supply
G = 100
+15VDC
x10
Span
Adjust
11
7
VFC32/
320/62
HCPL-
2731
Opto-
100Ω
INA102
10kΩ
IN914
6
10
Coupler
–15VDC
14
+15VDC
–In
9
+15VDC
4990Ω
15kΩ
Cold
Junction
Compensation
500Ω
–15VDC
OPA27
100kΩ
Zero Adjust
1MΩ
Up-Scale
Burn-Out
Indication
+VOFFSETTING
1MΩ
–15VDC
–15VDC
–15VDC
FIGURE 7. Isolated Thermocouple Amplifier with Cold Junction Compensation.
®
BB [ BURR-BROWN CORPORATION ]
