`H(s) = (1/(sqrt( R_1 R_2 C_1 C_2 )))^2 / ( "s" ^2 + 2 alpha "s" + (1/(sqrt( R_1 R_2 C_1 C_2 )))^2)`

Enter a value for all fields

This equation computes the transfer function H(s) for a unity gain low pass filter implementation of the Sallen-Key topology.  This electronic filter is a special case of a second-order unity gain filter version of the voltage-controlled voltage-source (VCVS) topology.

The angular frequency term in this equation is derived from the Resistances and Capacitances (`R_1, R_2, C_1, C_2`) shown in the diagram.

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Sallen-Key Calculators:

• Sallen-Key α filter 
• Sallen-Key Q Factor (ω₀ ,α) 
• Sallen-Key Q Factor (R&C) 
• Sallen-Key Unity Gain Low Pass Filter - Transfer Function
• Sallen-Key Unity Gain Low Pass Filter - Transfer Function (f0)
• Sallen-Key Unity Gain Low Pass Filter - Transfer Function (R&C)