ELECTRONIC DEVICE INCLUDING FILTER

摘要

An electronic device includes a main circuit connected between an input terminal and an output terminal, and an auxiliary circuit connected in parallel to the main circuit between the input terminal and the output terminal. The main circuit includes a filter having a first passband and a stopband. The auxiliary circuit has a passing characteristic that allows a signal having a frequency in a certain frequency band inside the stopband to pass through the auxiliary circuit. The main circuit is configured to output a main signal in response to an input signal. The auxiliary circuit is configured to output an auxiliary signal in response to the input signal. The main signal and the auxiliary signal contain phase components opposite to each other in the certain frequency band inside the stopband. This electronic device has an attenuation amount in the stopband.

主权项

1. An electronic device comprising:
an input terminal; an output terminal; a filter circuit connected between the input terminal and the output terminal and having a first phase characteristic, a first passband, and a first stopband, the filter circuit including a plurality of series arm resonators connected in series with one another along a signal line between the input terminal and the output terminal, and a plurality of parallel arm resonators connected between the signal line and a reference potential; and an auxiliary circuit connected in parallel with the filter circuit between the input terminal and the output terminal, the auxiliary circuit including a first capacitor element, a second capacitor element, and a resonator connected in series between the first capacitor element and the second capacitor element, the auxiliary circuit having an attenuation band within the first stopband and a second phase characteristic that is opposite to the first phase characteristic in the attenuation band.