Electrostatic shielding of planar magnetic devices of electrosurgical generators

Abstract

An electronic device includes: a multilayered dielectric substrate including a plurality of dielectric layers; a planar magnetic device disposed on at least one internal dielectric layer of the plurality of dielectric layers; and an overlapping shield assembly including a first shield layer and a second shield layer separated by at least one of the plurality of dielectric layers.

What is claimed is: 
     
         1 . An electronic device comprising:
 a multilayered dielectric substrate including a plurality of dielectric layers;   a planar magnetic device disposed on at least one internal dielectric layer of the plurality of dielectric layers; and   an overlapping shield assembly including a first shield layer and a second shield layer separated by at least one of the plurality of dielectric layers, the first shield layer having a plurality of first strips separated by a first plurality of gaps and the second shield layer having a plurality of second strips separated by a second plurality of gaps, the plurality of first strips and the plurality of second strips are parallel relative to each other with the first plurality of strips overlapping the second plurality of gaps and the second plurality of strips overlapping the first plurality of gaps.   
     
     
         2 . The electronic device according to  claim 1 , wherein each of the plurality of first strips has a first width and the plurality of first strips are separated by a first gap width. 
     
     
         3 . The electronic device according to  claim 2 , wherein each of the plurality of second strips has a second width and the plurality of second strips are separated by a second gap width. 
     
     
         4 . The electronic device according to  claim 3 , wherein the first width is substantially equal to the second gap width and the second width is substantially equal to the first gap width. 
     
     
         5 . The electronic device according to  claim 2 , wherein the first shield layer includes a first perimeter conductor coupled to each of the plurality of first strips and the second shield layer includes a second perimeter conductor coupled to each of the plurality of second strips. 
     
     
         6 . The electronic device according to  claim 5 , wherein the first shield layer is electrically coupled to the second shield layer. 
     
     
         7 . The electronic device according to  claim 1 , wherein the planar magnetic device is a sense transformer. 
     
     
         8 . The electronic device according to  claim 7 , wherein the sense transformer includes:
 a first outer coil configured to detect a first magnetic field generated by a current;   a second outer coil configured to detect the first magnetic field, the second outer coil further configured to cancel an electrical field induced in the first outer coil; and   an inner conductor disposed between the first outer coil and the second outer coil, the inner conductor configured to detect a second magnetic field generated by the current.   
     
     
         9 . The electronic device according to  claim 8 , wherein each of the first outer coil, the second outer coil, and the inner conductor is disposed on a corresponding internal dielectric layer of the plurality of dielectric layers. 
     
     
         10 . A current sensor comprising:
 a multilayered dielectric substrate including a plurality of dielectric layers;   at least one current sensing device disposed on at least one internal dielectric layer of the plurality of dielectric layers; and   an overlapping shield assembly including a first shield layer and a second shield layer separated by at least one of the plurality of dielectric layers, the first shield layer having a plurality of first strips separated by a first plurality of gaps and the second shield layer having a plurality of second strips separated by a second plurality of gaps, the plurality of first strips and the plurality of second strips are parallel relative to each other with the first plurality of strips overlapping the second plurality of gaps and the second plurality of strips overlapping the first plurality of gaps.   
     
     
         11 . The current sensor according to  claim 10 , wherein each of the plurality of first strips has a first width and the plurality of first strips are separated by a first gap width. 
     
     
         12 . The current sensor according to  claim 11 , wherein each of the plurality of second strips has a second width and the plurality of second strips are separated by a second gap width. 
     
     
         13 . The current sensor according to  claim 12 , wherein the first width is substantially equal to the second gap width and the second width is substantially equal to the first gap width. 
     
     
         14 . The current sensor according to  claim 11 , wherein the first shield layer includes a first perimeter conductor coupled to each of the plurality of first strips and the second shield layer includes a second perimeter conductor coupled to each of the plurality of second strips. 
     
     
         15 . The current sensor according to  claim 14 , wherein the first shield layer is electrically coupled to the second shield layer. 
     
     
         16 . The current sensor according to  claim 10 , wherein the at least one current sensing device includes:
 a first outer coil configured to detect a first magnetic field generated by a current being sensed;   a second outer coil configured to detect the first magnetic field, the second outer coil further configured to cancel an electrical field induced in the first outer coil; and   an inner conductor disposed between the first outer coil and the second outer coil, the inner conductor configured to detect a second magnetic field generated by the current being sensed.   
     
     
         17 . The current sensor according to  claim 16 , wherein each of the first outer coil, the second outer coil, and the inner conductor is disposed on a corresponding internal dielectric layer of the plurality of dielectric layers.