LMC6022 Datasheet, PDF (9/16 Pages) National Semiconductor (TI) – Low Power CMOS Dual Operational Amplifier

Application Hints (Continued)
DS011236-8
FIGURE 4. Example of Guard Ring in P.C. Board Layout (Using the LMC6024)
(a) Inverting Amplifier
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(b) Non-Inverting Amplifier
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(c) Follower
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(d) Howland Current Pump
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FIGURE 5. Guard Ring Connections
The designer should be aware that when it is inappropriate
to lay out a PC board for the sake of just a few circuits, there
is another technique which is even better than a guard ring
on a PC board: Don’t insert the amplifier’s input pin into the
board at all, but bend it up in the air and use only air as an in-
sulator. Air is an excellent insulator. In this case you may
have to forego some of the advantages of PC board con-
struction, but the advantages are sometimes well worth the
effort of using point-to-point up-in-the-air wiring. See Figure
6.
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