PIEZOELECTRIC BAND-PASS FILTER Russian patent published in 2014 - IPC H03H9/54 

FIELD: radio engineering, communication.

SUBSTANCE: piezoelectric band-pass filter includes a first piezoelectric resonator, a first capacitor, a second piezoelectric resonator, first and second inductance coils, as well as second, third, fourth and fifth capacitors, wherein the first inductance coil is connected to the second terminal of the first piezoelectric resonator and the first terminal of the second capacitor; the second terminal of the first inductance coil is connected to a common bus; the second terminal of the second capacitor is connected to the input potential terminal of the filter and the third capacitor, the second terminal of which is connected to the first terminal of the first piezoelectric resonator; the second terminal of the second piezoelectric resonator is connected to the fourth capacitor and the second inductance coil; the second terminal of the fourth capacitor is connected to the common bus; the second terminal of the second inductance coil is connected to the output potential terminal of the filter and the fifth capacitor, the second terminal of which is connected to the first terminal of the second piezoelectric resonator.

EFFECT: improved attenuation in the stop-band and improved matching with low-resistance equivalent loads.

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