LC circuits and filters

Abstract

An LC circuit and a filter are provided. The LC circuit includes a first capacitor disposed between a first connection point and a second connection point, a second capacitor disposed between the second connection point and a third connection point, a third capacitor disposed between the third connection point and a fourth connection point, a fourth capacitor disposed between the first connection point and the third connection point, a fifth capacitor disposed between the second connection point and the fourth connection point, a first inductor connected to the second connection point, and a second inductor connected to the third connection point.

Claims

1. An LC circuit, characterized in that, include: A first capacitor is disposed between the first connection point and the second connection point; A second capacitor is disposed between the second connection point and the third connection point; A third capacitor is disposed between the third connection point and the fourth connection point; A fourth capacitor is disposed between the first connection point and the third connection point; A fifth capacitor is disposed between the second connection point and the fourth connection point; The first inductor connected to the second connection point; and The second inductor connected to the third connection point, The first capacitor, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, the first inductor, and the second inductor constitute a high-pass filter. The high-pass filter, in the pass-through attenuation characteristics of the filter containing the high-pass filter, forms multiple attenuation poles in a frequency band lower than the passband of the filter.

2. The LC circuit according to claim 1, characterized in that: The first inductor is disposed between the second connection point and the ground wire. The second inductor is disposed between the third connection point and the ground wire.

3. The LC circuit according to claim 2, characterized in that: It also includes a third inductor disposed between the first inductor and the second inductor and the ground wire.

4. The LC circuit according to claim 1, characterized in that, Also includes: A sixth capacitor connected to the second connection point and in parallel with the first inductor; and A seventh capacitor connected to the third connection point and in parallel with the second inductor.

5. The LC circuit according to claim 1, characterized in that: The first connection point is connected to a first signal port used for signal input or output. The fourth connection point is connected to the second signal port used for input or output of the signal.

6. The LC circuit according to claim 5, characterized in that: The first connection point, the second connection point, the third connection point, and the fourth connection point are sequentially arranged on the signal path that connects the first signal port and the second signal port.

7. The LC circuit according to claim 5, characterized in that: At least one of the first connection point and the first signal port and the fourth connection point and the second signal port is provided with other circuits.

8. The LC circuit according to claim 1, characterized in that: It also includes a laminate for integrating the first capacitor, the second capacitor, the third capacitor, the fourth capacitor and the fifth capacitor with the first inductor and the second inductor, the laminate comprising a plurality of stacked dielectric layers and a plurality of conductor layers.

9. The LC circuit according to claim 8, characterized in that: The plurality of conductor layers include: a plurality of capacitor conductor layers for constituting the first capacitor, the second capacitor, the third capacitor, the fourth capacitor, and the fifth capacitor; and a plurality of inductor conductor layers for constituting the first inductor and the second inductor.

10. The LC circuit according to claim 9, characterized in that: The plurality of capacitor conductor layers include two capacitor conductor layers disposed at the same position in the stacking direction of the plurality of dielectric layers. The two capacitors are point-symmetric to each other using conductor layers.

11. The LC circuit according to claim 9, characterized in that: The plurality of conductor layers for inductors includes two conductor layers for inductors disposed at the same position in the stacking direction of the plurality of dielectric layers. The two inductors are point-symmetric to each other using conductor layers.

12. A filter, characterized in that, include: The first signal port and the second signal port are used for signal input or output, respectively; The signal path connecting the first signal port and the second signal port is provided with a first connection point, a second connection point, a third connection point and a fourth connection point in sequence. A first capacitor is disposed between the second connection point and the third connection point; A second capacitor is disposed between the first connection point and the third connection point; A third capacitor is disposed between the second connection point and the fourth connection point; A fourth capacitor is disposed between the first connection point and the second connection point; A fifth capacitor is disposed between the third connection point and the fourth connection point; The first inductor connected to the second connection point; and The second inductor connected to the third connection point, The first capacitor, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, the first inductor, and the second inductor constitute a high-pass filter. The high-pass filter, in its pass-through attenuation characteristics, forms multiple attenuation poles in a frequency band lower than the passband of the filter.

13. The filter according to claim 12, characterized in that: The first inductor is disposed between the second connection point and the ground wire. The second inductor is disposed between the third connection point and the ground wire.

14. The filter according to claim 13, characterized in that: It also includes a third inductor disposed between the first inductor and the second inductor and the ground wire.

15. The filter according to claim 12, characterized in that: At least one of the first connection point and the first signal port and the fourth connection point and the second signal port is provided with other circuits.

16. The filter according to claim 15, characterized in that: The other circuitry is a low-pass filter.

17. The filter according to claim 12, characterized in that, Also includes: A sixth capacitor connected to the second connection point and in parallel with the first inductor; and A seventh capacitor connected to the third connection point and in parallel with the second inductor.

18. The filter according to claim 12, characterized in that: It also includes a stack for integrating the first capacitor, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, the first inductor, and the second inductor, the stack comprising a plurality of stacked dielectric layers and a plurality of conductor layers.

19. The filter according to claim 18, characterized in that: The plurality of conductor layers include: a plurality of capacitor conductor layers for constituting the first capacitor, the second capacitor, the third capacitor, the fourth capacitor, and the fifth capacitor; and a plurality of inductor conductor layers for constituting the first inductor and the second inductor.

20. The filter according to claim 19, characterized in that: The plurality of capacitor conductor layers includes two capacitor conductor layers disposed at the same position in the stacking direction of the plurality of dielectric layers. The two capacitors are point-symmetric to each other using conductor layers.

21. The filter according to claim 19, characterized in that: The plurality of conductor layers for inductors includes two conductor layers for inductors disposed at the same position in the stacking direction of the plurality of dielectric layers. The two inductors are point-symmetric to each other using conductor layers.

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