Claims
- 1. A semiconductor device, comprising:a semiconductor chip having a coil and a capacitor defining an oscillating circuit with a resonant frequency; an electrically insulating layer forming a dielectric for said capacitor and covering said semiconductor chip; and an evaluation circuit connected to said oscillating circuit for detecting a detuning of said oscillating circuit due to a change in said resonant frequency caused by altering said electrically insulating layer, said evaluation circuit disabling said semiconductor chip upon detecting the detuning of said oscillating circuit.
- 2. The semiconductor device according to claim 1, wherein said semiconductor chip has a top surface, at least said coil being formed as a metallic conductor track over said top surface.
- 3. The semiconductor device according to claim 2, wherein said metallic conductor track includes parallel conductor track sections, said capacitor being formed by said parallel conductor track sections.
- 4. The semiconductor device according to claim 1, which further comprises at least a further oscillating circuit coupled to said oscillating circuit for oscillating.
- 5. The semiconductor device according to claim 1, wherein said semiconductor chip has a surface, said coil spanning said surface substantially entirely.
- 6. The semiconductor device according to claim 2, wherein said capacitor substantially entirely occupies said top surface at free surface areas thereof.
- 7. The semiconductor device according to claim 1, wherein said evaluation circuit, after application of said electrically insulating layer, ascertains said resonant frequency of said oscillating circuit and drives said oscillating circuit during an operation of said semiconductor chip.
- 8. The semiconductor device according to claim 1, wherein said evaluation circuit drives said oscillating circuit at a preset frequency.
- 9. The semiconductor device according to claim 1, wherein said electrically insulating layer forms a cover for said semiconductor chip, said evaluation circuit detecting the detuning of said oscillating circuit due to a removal of said cover.
Priority Claims (1)
Number |
Date |
Country |
Kind |
196 39 033 |
Sep 1996 |
DE |
|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of copending International Application PCT/DE97/02039, filed Sep. 11, 1997, which designated the United States.
US Referenced Citations (7)
Foreign Referenced Citations (3)
Number |
Date |
Country |
4018688A1 |
Jan 1991 |
DE |
196 39 033C1 |
Aug 1997 |
DE |
0378306A2 |
Jul 1990 |
EP |
Non-Patent Literature Citations (1)
Entry |
Published International Application No. 97/36326 (Cole et al.), dated Oct. 2, 1997. |
Continuations (1)
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Number |
Date |
Country |
Parent |
PCT/DE97/02039 |
Sep 1997 |
US |
Child |
09/274501 |
|
US |