In the figure we have a low-pass filter, with a cutoff frequency of 10 kHz, also suggested by National Semiconductor in its linear applications manual. The values of components C1 and C2 that determine the cutoff frequency can be changed. These values, of numerical series that the reader may find strange, are of low tolerances. Commercial values of common 5% series can be used, if the tolerance of the project allows it. The power supply is symmetrical and the LM102 operational amplifier can be replaced with equivalents. The reader must also be aware of the maximum frequency that the operational amplifier used can operate.
