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These tables are a guide to the more common op-amp circuits. Table 3.1 contains circuits which convert a signal from one form to another. Table 3.2 is a selection of circuits for conditioning voltage signals. The circuit numbers used in the tables refer to the circuit numbers used in section 4 of the data sheet.

Table 3.1. Signal conversion circuits.

Table 3.2. Circuits for conditioning voltage signals

Requirement	Solution
To amplify a voltage signal	and invert; use circuit 1 uninverted; high impedance input; To amplify a use circuit 2 and invert; use circuit 3 uninverted; high impedance input; use circuit 4
To attenuate a signal	Use ccts 1 or 3 (min. gain in circuits 2 and 4 is 1). Use two in series for a noninverting attenuator.
To add two signals & amplify the sum	Circuit 6 gives a uniformly weighted sum, circuit 7 a weighted sum.
To subtract two signals and amplify the difference	Circuit 8 amplifies a simple difference, and 9 a weighted difference.
To pass only selected frequencies from a signal (i.e. filtering action).	All those below a specified frequency, use circuit 10. All those above a specified frequency, use circuit 11. All those within a specified band, use circuit 12. All those outside a specified band, use circuit 13.
To precision rectify (i.e. convert from AC to DC)	Circuit 14.
To integrate a signal	Circuit 15.
To differentiate a signal	Circuit 16.
To compare two voltages and indicate which is largest	Circuit 17.

Note: Circuits 9 - 12 are first order filters. See Reference 1 for filters with a higher specification.