What Sallen-Key Filter Articles Don't Tell You - Part III
by Dave Van Ess, Principal Application Engineer, Cypress Semiconductor

Part II in this series showed the effect that op amp bandwidth and output impedance has on Sallen-Key filter performance. The remaining effect to consider is noise.

For a better understanding of noise in op amp circuits I recommend:

• Linear Technology's Design Note 15 (Noise Calculations in Op Amp Circuits)
• The analogZONE TechNote by TI's Art Kay (Analysis and Measurement of Intrinsic Noise in Op Amp Circuits)

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