Signal conditioning: Filters beyond coffee
A five-page application note from Dataforth Corp. reviews signal-conditioning filter fundamentals. While hundreds of articles and text books have been written on filters that provide a multitude of frequency characteristics such as the Bessel, Butterworth, Chebyshev, Cauer, etc., the objective of this application note is a brief review of filter fundamentals primarily focused on the amplitude response of low-pass (LP) filters needed in industrial signal conditioning modules.
Signal conditioning modules (SCMs), used for measuring process control variables such as temperature, pressure, strain, position, speed, and level, are always subject to externally induced noise signals. Field sensors with output voltages in the millivolt range are certainly degraded by induced noise levels on the order of volts. Consequently, signal conditioning modules must provide filtering to eliminate induced noise components.
“Filtering in Signal Conditioning” (AN112, 455kb pdf)
— Edited by C.G. Masi , senior editor
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