lmc6462bimx National Semiconductor Corporation, lmc6462bimx Datasheet - Page 14

• Manufacturer Part Number: lmc6462bimx
• Description: Micropower, Rail-to-rail Input And Output Cmos Operational Amplifier
• Manufacturer: National Semiconductor Corporation

www.national.com
Application Information
(Input pins are lifted out of PC board and soldered directly to components.
All other pins connected to PC board.)
A two op-amp instrumentation amplifier designed for a gain
of 100 is shown in Figure 15. Low sensitivity trimming is
made for offset voltage, CMRR and gain. Low cost and low
power consumption are the main advantages of this two
op-amp circuit.
FIGURE 13. Air Wiring
FIGURE 14. Low Power Three Op-Amp Instrumentation Amplifier
(Continued)
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8.0 INSTRUMENTATION CIRCUITS
The LMC6464 has the high input impedance, large common-
mode range and high CMRR needed for designing instru-
mentation circuits. Instrumentation circuits designed with the
LMC6464 can reject a larger range of common-mode signals
than most in-amps. This makes instrumentation circuits de-
signed with the LMC6464 an excellent choice for noisy or
industrial environments. Other applications that benefit from
these features include analytic medical instruments, mag-
netic field detectors, gas detectors, and silicon-based trans-
ducers.
A small valued potentiometer is used in series with R
the differential gain of the three op-amp instrumentation
circuit in Figure 14. This combination is used instead of one
large valued potentiometer to increase gain trim accuracy
and reduce error due to vibration.
Higher frequency and larger common-mode range applica-
tions are best facilitated by a three op-amp instrumentation
amplifier.
01205120
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