Two-channel center-frequency-adjustable band-pass filter

Abstract

The invention belongs to the technical field of circuit design, and relates to a two-channel center-frequency-adjustable band-pass filter. The two-channel center-frequency-adjustable band-pass filtercomprises a signal input interface, a signal output interface, a band-pass filter circuit, a single chip microcomputer minimal system and a serial port burning interface and is characterized in that the input end of the band-pass filter circuit obtains input signals through the signal input interface; the output end outputs the filtered signals through the signal output interface; the single chipmicrocomputer minimal system is connected with the serial port burning interface and obtains the complied program through the serial port burning interface; the clock frequency input port of the band-pass filter circuit is connected with the clock frequency output port of the single chip microcomputer minimal system; different clock frequency is obtained. The clock frequency is output through thesingle chip microcomputer minimal so as to control the center frequency of the band-pass filter; the center frequency of the band-pass filter module can be fast regulated; the precision is high; the filtering effect is good and stable.

Description

technical field [0001] The invention relates to a band-pass filter with adjustable center frequency of two channels, which belongs to the technical field of circuit design. Background technique [0002] In circuit design, the high-frequency noise generated by the switching of electronic components and the interference noise introduced during the signal acquisition process are unavoidable. If they are not filtered in time, the noise will affect the stability of the circuit system. [0003] A traditional band-pass filter is composed of an RC low-pass filter and an RC high-pass filter. The RC values ​​of the low-pass filter and the high-pass filter are respectively matched to obtain the upper limit cut-off frequency and the lower limit cut-off frequency, thereby obtaining a band-pass filter. Once the RC values ​​of the low-pass filter and high-pass filter are determined, the center frequency is fixed and cannot be modified. If you need to modify the center frequency, the proc...

AI Technical Summary

Problems solved by technology

Once the RC values ​​of the low-pass filter and high-pass filter are determined, the center frequency is fixed and cannot be modified

If you need to modify the center frequency, the process is very time-consuming, and you need to re-solder a new resistor R and capacitor C with an electric soldering iron

Moreover, due to the error in the resistance value of the resistor and the capacitance value itself, there is a large deviation between the actual center frequency and the theoretical center frequency, resulting in poor filtering effect.

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