United States Patent [19] [ii] Patent Number: 4,578,654
Tait [45] Date of Patent: Mar. 25, 1986
[54] DISTRIBUTED CAPACITANCE LC RESONANT CIRCUIT
[75] Inventor: William C. Tait, Oak Park Heights, Minn.
[73] Assignee: Minnesota Mining and
Manufacturing Company, St. Paul,
Minn.
[21] Appl. No.: 552,305
[22] Filed: Nov. 16,1983
[51] Int. CI.4 H03H 7/01
[52] U.S. CI 333/175; 333/167;
333/185; 333/219
[58] Field of Search 333/167, 175, 177, 184,
333/185, 174, 168, 138-140, 219; 336/200;
340/552, 553, 568, 571, 573
[56] References Cited
U.S. PATENT DOCUMENTS
2,584,592 2/1952 Kehbel 336/200 X
2,911,605 11/1959 Wales, Jr 336/200
3,413,716 12/1968 Schwertz et al 336/200 X
3,436,687 4/1969 Andrews, Jr. et al 336/200 X
3,810,147 5/1974 Lichtblau 340/280
3,863,244 1/1975 Lichtblau 340/280
3,913,219 10/1975 Lichtblau 29/592
3,967,161 6/1976 Lichtblau 340/572 X
4,021,705 5/1977 Lichtblau 361/402
4,322,698 3/1982 Takahashi et al 333/184
4,369,557 1/1983 Vandebult 29/25.42
FOREIGN PATENT DOCUMENTS
164435 2/1953 Australia 336/200
WO83/01697 5/1983 PCT Int'l Appl. .
Primary Examiner—Marvin L. Nussbaum
Attorney, Agent, or Firm—Donald M. Sell; James A.
Smith; William B. Barte
[57] ABSTRACT
A tuned resonant circuit including inductive and capacitive components useful as a marker in electronic marker surveillance systems, comprising a laminate of a dielectric and conductive-multi-turn spirals on opposing surfaces of the dielectric, wherein the capacitive component is formed as a result of distributed capacitance between the opposed spirals, and wherein an electrical connection is provided between predetermined opposing portions of the respective spirals.
10 Claims, 12 Drawing Figures
