Temperature compensated capacitor
AssigneeFiltronic Components Limited
InventorsChristopher I. Mobbs, J. David Rhodes
Life of this patent
Estimating the term…
Abstract
A temperature compensating capacitor device is described. The device incorporates at least two capacitors with different dielectric materials which vary with temperature such that the overall capacitance of the device remains substantially constant. Filter circuits incorporating such devices and methods of making them are described. Capacitors of one dielectric material are formed by etching a conductive coating on one face of a layer of that material. The layer is attached via a conductive coating on its other face to the base of a housing, and capacitors of the other dielectric material are attached to its etched face. Other impedances are attached between the capacitors to form the ladder network.
Claims9
A method of making a filter device for producing a desired frequency response, the method comprising the steps of:
- taking a sheet of a first dielectric material having a coating of conductive material on both faces;
- etching away the conductive material on one face of said sheet to define a first set of capacitors between opposed conductive areas of said faces;
- attaching said sheet at its unetched face to the base of a housing;
- attaching a second set of capacitors having a second dielectric material different to that of said first dielectric material to said conductive areas on said etched face of said sheet;
- and
- connecting inductive impedances from said housing, respectively, to said second set of capacitors to form a ladder type filter circuit of adjacent circuit sections each comprising one capacitor of said first set, one capacitor of said second set, and one of said impedances.
Dependencies are inferred from the claim text.