Tunable Bandpass Filter Circuit. Band pass filter circuit. Block diagram of active band pass filter.
An spi tunable second order filter the figure 1 circuit is a state variable second order filter using two ics a low noise cmos quad op amp ltc6242 and a low noise dual programable gain amplifier pga ltc6912 x. The 3 db filter bandwidth is approximately 15 of the center frequency f center and the 20 db filter bandwidth is 37. Block diagram of active band pass filter.
Passive or active a bandpass filter allows a certain range of frequencies to pass through and greatly attenuates all frequencies outside of this passband.
Then the op amp is used for the. Passive or active a bandpass filter allows a certain range of frequencies to pass through and greatly attenuates all frequencies outside of this passband. The gains of the two ltc6912 x amplifiers ga and gb are independently programmed via spi control. It can be integrated into dif ferent projects including software defined radio sdr projects where the band pass filters are of fundamental importance to the end result.
