Abstract: A filter includes: a piezoelectric substrate; a first acoustic wave resonator located on the piezoelectric substrate and including a pair of first reflectors including first grating electrodes and a pair of first comb-shaped electrodes that is located between the first reflectors and includes first electrode fingers; and a second acoustic wave resonator that is connected in series or parallel with the first acoustic wave resonator, is located on the piezoelectric substrate, and includes a pair of second reflectors including second grating electrodes and a pair of second comb-shaped electrodes that is located between the second reflectors and includes second electrode fingers, an average value of duty ratios of the second grating electrodes being different from an average value of duty ratios of the first grating electrodes, an average value of pitches of the second electrode fingers being substantially equal to an average value of pitches of the first electrode fingers.

Abstract: A filter includes: a piezoelectric substrate; a first acoustic wave resonator located on the piezoelectric substrate and including a pair of first reflectors including first grating electrodes and a pair of first comb-shaped electrodes that is located between the first reflectors and includes first electrode fingers; and a second acoustic wave resonator that is connected in series or parallel with the first acoustic wave resonator, is located on the piezoelectric substrate, and includes a pair of second reflectors including second grating electrodes and a pair of second comb-shaped electrodes that is located between the second reflectors and includes second electrode fingers, an average value of duty ratios of the second grating electrodes being different from an average value of duty ratios of the first grating electrodes, an average value of pitches of the second electrode fingers being substantially equal to an average value of pitches of the first electrode fingers.

Abstract: An oscillator includes a first oscillating portion that outputs a first oscillation signal having a first oscillation frequency through a first intermediate node to an output terminal, a mounting portion that includes an insulating layer and that mounts the first oscillating portion, a first line provided in the insulating layer and coupled between the first intermediate node and ground, a second line provided in the insulating layer and coupled between the first intermediate node and a power supply terminal, and a third line provided in the insulating layer and coupled between the first intermediate node and the output terminal.

Abstract: An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.

Abstract: The present invention is an oscillator including: first transistors outputting oscillation signals of different oscillation frequencies to collectors; a common node to which outputs of emitters of the first transistors are connected and input; a feedback circuit feeding an output of the common node to bases of the first transistors; and isolation circuits that are respectively provided between the emitters of the first transistors and the common node and cut off high frequency components from the common node.

Abstract: The present invention is an oscillator including: a first resonance circuit including a first variable capacitance diode having a cathode connected to a control terminal, a first capacitor and a first inductor connected between an anode of the first variable capacitance diode and ground; a second resonance circuit including a second variable capacitance diode having a cathode connected to the control terminal, a second capacitor and a second inductor connected between an anode of the second variable capacitance diode and ground; and an oscillation circuit coupled to the first and second resonance circuits and outputting an oscillation output.

Abstract: An oscillator includes a first oscillating portion that outputs a first oscillation signal having a first oscillation frequency through a first intermediate node to an output terminal, a mounting portion that includes an insulating layer and that mounts the first oscillating portion, a first line provided in the insulating layer and coupled between the first intermediate node and ground, a second line provided in the insulating layer and coupled between the first intermediate node and a power supply terminal, and a third line provided in the insulating layer and coupled between the first intermediate node and the output terminal.

Abstract: The present invention is an oscillator including: a first resonance circuit including a first variable capacitance diode having a cathode connected to a control terminal, a first capacitor and a first inductor connected between an anode of the first variable capacitance diode and ground; a second resonance circuit including a second variable capacitance diode having a cathode connected to the control terminal, a second capacitor and a second inductor connected between an anode of the second variable capacitance diode and ground; and an oscillation circuit coupled to the first and second resonance circuits and outputting an oscillation output.

Abstract: The present invention is an oscillator including: first transistors outputting oscillation signals of different oscillation frequencies to collectors; a common node to which outputs of emitters of the first transistors are connected and input; a feedback circuit feeding an output of the common node to bases of the first transistors; and isolation circuits that are respectively provided between the emitters of the first transistors and the common node and cut off high frequency components from the common node.

Abstract: An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.