Consider the following transfer functions of Sallen-Key filters.
\({H_1}\left( s \right) = \frac{{{a_0}}}{{{b_2}{s^2} + {b_1}s + {b_0}}}\)
\({H_2}\left( s \right) = \frac{{{a_2}{s^2}}}{{{b_2}{s^2} + {b_1}s + {b_0}}}\)
\({H_3}\left( s \right) = \frac{{{a_1}s}}{{{b_2}{s^2} + {b_1}s + {b_0}}}\)
Which of the following is/are true?
1
H1(s) represents Low pass Sallen-Key filter
2
H2(s) represents band reject Sallen-Key filter
3
H3(s) represents band pass Sallen-Key filter
4
H2(s) represents High pass Sallen-Key filter