Chapter 1 Flat (Butterworth) Active Filter Texas Instrument’s SLOA024B, “Analysis of Sallen-Key Architecture” shows the circuit below. It is a 2nd-order active low-pass filter. The following transfer function is given: If R4 = 0, and R3 is open, then K =1....
More
Chapter 1 Flat (Butterworth) Active Filter Texas Instrument’s SLOA024B, “Analysis of Sallen-Key Architecture” shows the circuit below. It is a 2nd-order active low-pass filter. The following transfer function is given: If R4 = 0, and R3 is open, then K =1. The circuit reduces to this: The equation above reduces to: ???????? 1 = 2 ???????? ???? (????1 ????2????1 ????2 ) + ????????1 (????1 + ????2 ) + 1 Define the denominator of this equation as: ????(????) = ???? 2 (????1 ????2 ????1 ????2 ) + ????????1 (????1 + ????2 ) + 1. To simplify the design, set ????1 = ????2 = ???? . ????(????) = ???? 2 (???? 2 ????1 ????2 ) + 2????????????1 + 1. Chapter 1 Author: James F. Balicki Page 1
Less
