LT1996
Precision, 100µA
Gain Selectable Amplifier
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FEATURES
DESCRIPTIO
The LT®1996 combines a precision operational amplifier
with eight precision resistors to form a one-chip solution
for accurately amplifying voltages. Gains from –117 to
118withagainaccuracyof0.05%canbeachievedwithout
any external components. The device is particularly well
suitedforuseasadifferenceamplifier, wheretheexcellent
resistor matching results in a common mode rejection
ratio of greater than 80dB.
■
Pin Configurable as a Difference Amplifier,
Inverting and Noninverting Amplifier
■
Difference Amplifier
Gain Range 9 to 117
CMRR >80dB
■
Noninverting Amplifier
Gain Range 0.008 to 118
■
Inverting Amplifier
Gain Range –0.08 to –117
The amplifier features a 50µV maximum input offset
voltage and a gain bandwidth product of 560kHz. The
device operates from any supply voltage from 2.7V to 36V
and draws only 100µA supply current on a 5V supply. The
output swings to within 40mV of either supply rail.
■
Gain Error: <0.05%
■
Gain Drift: < 3ppm/°C
■
Wide Supply Range: Single 2.7V to Split ±18V
■
Micropower Operation: 100µA Supply
■
Input Offset Voltage: 50µV (Max)
■
The internal resistors have excellent matching character-
istics; variation is 0.05% over temperature with a guaran-
teedmatchingtemperaturecoefficentoflessthan3ppm/°C.
The resistors are also extremely stable over voltage,
exhibiting a nonlinearity of less than 10ppm.
Gain Bandwidth Product: 560kHz
■
Rail-to-Rail Output
■
Space Saving 10-Lead MSOP and DFN Packages
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APPLICATIO S
The LT1996 is fully specified at 5V and ±15V supplies and
from –40°C to 85°C. The device is available in space
saving 10-lead MSOP and DFN packages. For an amplifier
with selectable gains from –13 to 14, see the LT1991 data
sheet.
■
Handheld Instrumentation
■
Medical Instrumentation
■
Strain Gauge Amplifiers
■
Differential to Single-Ended Conversion
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners. Patents Pending.
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TYPICAL APPLICATIO
Rail-to-Rail Gain = 9 Difference Amplifier
Distribution of Resistor Matching
V
= V
+ 9 • ∆V
OUT
REF IN
40
35
30
25
20
15
10
5
15V
LT1996A
G = 81
SWING 40mV TO
EITHER RAIL
450k/81
450k/27
450k
4pF
450k/9
–
+
V
M(IN)
–
+
∆V
IN
450k/9
V
P(IN)
LT1996
450k
450k/27
INPUT RANGE
±60V
450k/81
R
= 100kΩ
4pF
IN
0
0
–0.04
–0.02
0.02
0.04
V
REF
RESISTOR MATCHING (%)
1996 TA01
–15V
1996 TA01b
1996f
1