Multiple level spiral inductors used to form a filter in a printed circuit board

A filter comprising:

• dielectric layers;
• at least three spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• a ground plane region formed on an external surface of the dielectric layers;
• a transmission line provided on one of the dielectric layers between two of the spiral inductors;
• a first via electrically connecting internal ends of the spiral inductors to the transmission line;
• a second via connecting the transmission line to the ground plane region;
• and
• a structure formed on a dielectric layer with the ground plane region, the structure comprising:
• a second transmission line having one end connected to the second via;
• and
• a plurality of conductive lines connecting the second transmission line to the ground plane region.

A filter comprising:

• dielectric layers;
• and
• at least three spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• wherein the at least three spiral inductors comprise:
• a first pair of spiral inductors which substantially overlap;
• and
• a second pair of spiral inductors which substantially overlap, wherein the second pair of spiral inductors substantially do not overlap with the first pair of spiral inductors.

A filter comprising:

• dielectric layers;
• at least three spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• a via electrically connecting the internal ends of the spiral inductors;
• a first pair of transmission lines forming input terminals for the filter, one of the first pair being connected to the via, and another one of the first pair being electrically connected to a first one of the spiral inductors at a point separate from the via;
• and
• a second pair of transmission lines forming output terminals for the filter, one of the second pair being connected to the via, and another one of the second pair being electrically connected to a second one of the spiral inductors at a point separate from the via.

A filter comprising:

• dielectric layers;
• spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• ground plane regions formed on external surfaces of the dielectric layers;
• and
• a first via electrically connecting the spiral inductors to the ground plane regions.

A filter comprising:

• dielectric layers;
• spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• vias electrically connecting the spiral inductors to at least one external surface of the dielectric layers;
• and
• first lumped elements provided on at least one of the external surfaces of the dielectric layers, wherein the first lumped elements electrically connect the vias.

A filter comprising:

• dielectric layers;
• spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from each one of the spiral inductors to at least one of the other spiral inductors;
• ground plane regions formed on external surfaces of the dielectric layers;
• vias electrically connecting the spiral inductors to an external surface of the dielectric layers;
• and
• lumped elements provided on at least one external surface of the dielectric layers, the lumped elements electrically connecting the vias to at least one of the ground plane regions.

A filter comprising:

• dielectric layers;
• spiral inductors formed between different ones of the dielectric layers, wherein the spiral inductors are located to establish mutual inductance from one of the spiral inductors to another;
• a ground plane region formed on an external surface of the dielectric layers;
• a transmission line provided on one of the dielectric layers between two of the spiral inductors;
• a first via electrically connecting the spiral inductors to the transmission line;
• and
• a second via coupling the transmission line to the ground plane region.

A filter comprising:

• dielectric layers;
• a first pair of spiral inductors formed on different ones of the dielectric layers and substantially overlapping to establish mutual inductance;
• and
• a second pair of spiral inductors formed on different ones of the dielectric layers and substantially overlapping to establish mutual inductance, wherein the second pair of spiral inductors substantially do not overlap with the first pair of spiral inductors.