Question

Find the complex equation for the gain of the first order low pass butterworth filter as a function of frequency.

(a) AF/[1+j(f/fH)].

(b) AF/√ [1+j(f/fH)^2].

(c) AF×[1+j(f/fH)].

(d) None of the mentioned

I got this question during a job interview.

This intriguing question comes from First Order Low Pass Butterworth Filter in division Active Filters of Linear Integrated Circuits

Answer 1

Correct option is (a) AF/[1+j(f/fH)].

Illuminate the topic with: Gain of the filter, as a function of frequency is given as VO/ Vin=A F/(1+j(f/fH)).