LMC6484AIMX Datasheet, PDF (16/24 Pages) Texas Instruments – LMC6484 CMOS Quad Rail-to-Rail Input and Output Operational Amplifier

Application Information (Continued)
FIGURE 14. Operating from the same
Supply Voltage, the LMC6484 buffers the
ADC12038 maintaining excellent accuracy
DS011714-28
10.0 Instrumentation Circuits
The LMC6484 has the high input impedance, large
common-mode range and high CMRR needed for designing
instrumentation circuits. Instrumentation circuits designed
with the LMC6484 can reject a larger range of
common-mode signals than most in-amps. This makes in-
strumentation circuits designed with the LMC6484 an excel-
lent choice for noisy or industrial environments. Other appli-
cations that benefit from these features include analytic
medical instruments, magnetic field detectors, gas detectors,
and silicon-based transducers.
A small valued potentiometer is used in series with Rg to set
the differential gain of the 3 op-amp instrumentation circuit in
Figure 15. This combination is used instead of one large
valued potentiometer to increase gain trim accuracy and
reduce error due to vibration.
DS011714-29
FIGURE 15. Low Power 3 Op-Amp Instrumentation Amplifier
15
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