+VS
7
fC 0.75 Hz HPF
U1
1MΩ
50kΩ
50kΩ
2
VI–N
V
O = (VI+N – VI–N) + VREF
2.7778kΩ
6
VO
A1
52.6316kΩ
1MΩ
3
VI+N
1MΩ
INA148
0.22µF
+VS
1
4
–VS
7
6
U2:
2
OPA132 for VS = ±5V to ±15V
OPA340 for VS = ±2.5
U2
4
VREF
3
–VS
FIGURE 6. Quasi-AC-Coupled Differential Amplifier.
+5V
7
0.1µF
1MΩ
50kΩ
50kΩ
2
VI–N
V
O = (VI+N – VI–N) + 1.235V
2.7778kΩ
6
VO
VCM = –23V to +56V
A1
52.6316kΩ
1MΩ
3
VI+N
INA148
34kΩ
4
1
5Ω
+5V
+
10µF
REF1004-1.2
FIGURE 7. Single-Supply Differential Amplifier.
RS
IC
0.01Ω
+
–
0.1µF
50kΩ
28V
Supply
7
1MΩ
50kΩ
2
2.7778kΩ
VO = 1.235V + (IC • RS)
6
A1
52.6316kΩ
1MΩ
3
271kΩ
INA148
5Ω
4
1
+
10µF
REF1004-1.2
FIGURE 8. Battery Monitor Circuit.
®
11
INA148
BB [ BURR-BROWN CORPORATION ]
