Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
In a simple RC filter, the -3dB point is just the frequency where the resistance of the resistor equals the reactance of the capacitor R = [1 / (2 * pi * f* C)]. Then, for example, for an RC high-pass filter the output would then be Vo = Vin [R / (R+ 1/(2*pi*f*C))] where f is the -3dB frequency.
Is your deduction meaning attenuation? If yes, please see below.
When you have a simple transfer function like H(s) = 1/(1+sRC). That means |H(jw)|=1/sqrt(1+(wRC)^2).
At DC (f=0), |H(jw)| = 1.
At -3dB frequency, which w = 1/RC, you can deduct that |H(jw)| = 1/sqrt(2), which is -3dB.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
