Datasheet

2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
2
4 6 8 10 12 14 16 18
V
OUT
(V)
V
SENSE
(mV)
20
Actual
Ideal
Low V
SENSE
Case 2: V
SENSE
< 20 mV, 0 V ≤ V
CM
≤ V
S
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
2 4 6 8
10 12 14 16 18 20 22
V
OUT
(V)
V
SENSE
(mV)
24
INA195, INA198 V
OUT
Tested Limit
(1)
V
CM2
V
CM3
V
CM4
V
CM2
, V
CM3
, and V
CM4
illustrate the variance
from part to part of the V
CM
that can cause
maximum V
OUT
with V
SENSE
< 20mV.
V
OUT
tested limit at
V
SENSE
= 0mV, 0
≤
V
CM1
≤
V
S.
NOTE: (1) INA193, INA196 V
OUT
Tested Limit = 0.4V.
INA194, INA197 V
OUT
Tested Limit = 1V.
Ideal
V
CM1
INA193A-Q1 , INA194A-Q1 , INA195A-Q1
INA196A-Q1 , INA197A-Q1 , INA198A-Q1
SBOS366C – AUGUST 2006 – REVISED OCTOBER 2008 ............................................................................................................................................... www.ti.com
Figure 2. Example for Low V
SENSE
Cases 1 and 3
(INA195A, INA198A: Gain = 100)
This region of operation is the least accurate for the INA193A – INA198A family. To achieve the wide input
common-mode voltage range, these devices use two op amp front ends in parallel. One op amp front end
operates in the positive input common-mode voltage range, and the other in the negative input region. For this
case, neither of these two internal amplifiers dominates and overall loop gain is very low. Within this region, V
OUT
approaches voltages close to linear operation levels for Normal Case 2. This deviation from linear operation
becomes greatest the closer V
SENSE
approaches 0 V. Within this region, as V
SENSE
approaches 20 mV, device
operation is closer to that described by Normal Case 2. Figure 3 illustrates this behavior for the INA195A. The
V
OUT
maximum peak for this case is tested by maintaining a constant V
S
, setting V
SENSE
= 0 mV and sweeping
V
CM
from 0 V to V
S
. The exact V
CM
at which V
OUT
peaks during this test varies from part to part, but the V
OUT
maximum peak is tested to be less than the specified V
OUT
tested limit.
Figure 3. Example for Low V
SENSE
Case 2
(INA195A, INA198A: Gain = 100)
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Product Folder Link(s): INA193A-Q1 INA194A-Q1 INA195A-Q1 INA196A-Q1 INA197A-Q1 INA198A-Q1