Microcircuit package with integrated acoustic isolator

• US 5,650,685 A
• Filed: 09/25/1995
• Issued: 07/22/1997
• Est. Priority Date: 01/30/1992
• Status: Expired due to Fees

• Current Assignee: United States Department of the Army
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Layden, Owen P., Baidy, Edward R., Kosinski, John A., Ballato, Arthur
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US08/533,043
• Time in Patent Office: 666 Days
• Field of Search: 310/316-319, 310/311, 310/322, 310/334, 333/186-192
• US Class Current: 310/316.01
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/19107 off-chip wires
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H10N 30/40 with electrical input and electrical output, e.g. functioning as transformers

Abstract

A microcircuit package with an integrated acoustic isolator made up of a stacked acoustic filter. The package includes a rigid, electrically conductive housing with a IC module mounted therein. The acoustic filter includes two electroacoustic transducers mounted on opposite sides of a common wall of the package, one inside the package and the other outside. An a.c. power source is connected to the transducer that is mounted on the outside of the package. Electrical energy from the power source is converted by the outside transducer into acoustic energy which is conducted through the package wall to the inside transducer which reconverts the acoustic energy into electrical energy. The package wall has a significant thickness in comparison to the acoustic wavelength of the filter passband and is preferably equal to an integer number of one-half acoustic wavelengths. The transducer-wall combination acts as a filter having a passband tailored to prevent high-power microwave energy from being transmitted through the package wall.

Claims

1. A microcircuit package for isolation against high power microwave energy electromagnetic interference comprising:

an acoustically permeable, conductive barrier disposed as part of a conductive housing, the conductive housing having an outside and an inside;

a d.c. power source disposed outside the conductive housing;

means to convert d.c. power to a.c. power connected to the d.c. power source;

means to convert a.c. power to d.c. power;

at least a first and second planar piezoelectric plates mounted such that the first planar piezoelectric plate is mounted on the outside of the housing at the acoustically permeable barrier and is electrically connected to the d.c. to a.c conversion means and such that the second planar piezoelectric plate is oppositely mounted inside the housing and is electrically connected to the a.c. to d.c. conversion means;

integrated circuit means electrically connected to said a.c. to d.c. conversion means; and

data transmission and reception means electrically connected to the integrated circuit for providing an input signal to the integrated circuit means;

wherein said first planar piezoelectric plate converts a.c. power to acoustic power and the acoustic power then propagates across the acoustically permeable, conductive barrier;

wherein said barrier has a thickness which is greater than the first and second planar piezoelectric plates and is substantially equal to a multiple of one half the wavelength of said acoustic power;

and wherein said second planar piezoelectric plate converts the acoustic power propagating across the barrier back to a.c. power.

2. The microcircuit of claim 1 wherein said barrier is a grounded conductor.

3. The microcircuit package of claim 2 wherein said barrier is rigid and heavily loaded.

4. The microcircuit package of claim 3 wherein said barrier is selected from the group consisting of silver (Ag), aluminum (Al), brass, copper (Cu), Kovar, nickel (Ni), and steel.