Circuit Theory-2 #20 | Frequency Response and Decibels

Instructor: Dr. Süleyman Burak ÇELİK

In this Circuit Theory-2 lesson we take the transfer function H(s) from the previous lesson and read it on the imaginary axis as H(j omega): the frequency response. You will learn: - Why frequency response is H(s) evaluated at s = j omega - How magnitude gives gain and angle gives phase shift - Why a sinusoidal steady-state output keeps the same frequency - How to derive the RC low-pass frequency response - How to read magnitude and phase for the RC low-pass - Why engineers use decibels for amplitude ratios - How the -3 dB point and corner frequency appear on a Bode plot - Common traps: Hz vs rad/s, 20 log vs 10 log, phase sign, and steady-state assumptions Timestamps: 00:00 Frequency response and decibels 00:03 From transfer function to frequency behavior 00:36 Definition: H(j omega) 01:04 Sinusoidal steady-state rule 01:33 RC low-pass frequency response 02:06 Magnitude and phase 02:38 Decibels 03:12 Bode magnitude reading 03:42 Common traps 04:12 Wrap Next lesson: low-pass and high-pass filters using magnitude, phase, and Bode plots. Part of the Circuit Theory-2 playlist by AcEdumy.