Card-type electronic device with plastic frame sandwiched between printed circuit board and metal panel

• US 5,742,479 A
• Filed: 02/14/1996
• Issued: 04/21/1998
• Est. Priority Date: 03/09/1994
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Asakura, Tohru
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): Gandhi, Jayprakash N.
• Application Number:
  US08/601,459
• Time in Patent Office: 797 Days
• Field of Search: 361/730, 361/736, 361/737, 361/740, 361/741, 361/752, 361/756, 361/796, 361/799, 361/800, 361/802, 361/816, 361/818, 439/55, 439/60, 439/62, 174/35 GC, 174/35 R
• US Class Current: 361/737
• CPC Class Codes: G06K 13/077 with intermittent movement; Braking or stopping movement
• CPC Class Codes: G06K 19/077 Constructional details, e.g. mounting of circuits in the carrier
• CPC Class Codes: G06K 19/07735 the record carrier comprising means for protecting against electrostatic discharge
• CPC Class Codes: G06K 19/07743 External electrical contacts
• CPC Class Codes: H01R 12/721 cooperating directly with the edge of the rigid printed circuits
• CPC Class Codes: H01R 13/64 Means for preventing incorrect coupling
• CPC Class Codes: H01R 13/642 by position or shape of contact members
• CPC Class Codes: H05K 1/0225 Single or multiple openings in a shielding, ground or power plane H05K1/0227 takes precedence
• CPC Class Codes: H05K 1/0271 Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion
• CPC Class Codes: H05K 2201/068 wherein the coefficient of thermal expansion is important
• CPC Class Codes: H05K 2201/0969 Apertured conductors
• CPC Class Codes: H05K 2201/2072 Anchoring, i.e. one structure gripping into another
• CPC Class Codes: H05K 3/38 Improvement of the adhesion between the insulating substrate and the metal
• CPC Class Codes: H05K 3/4641 having integrally laminated metal sheets or special power cores
• CPC Class Codes: H05K 5/0269 Card housings therefor, e.g. covers, frames, PCB
• CPC Class Codes: H05K 9/0039 Galvanic coupling of ground layer on printed circuit board [PCB] to conductive casing printed shielding conductors, ground planes or power planes for reduction of cross-talk or noise in printed circuits H05K1/0218

Abstract

A card-type electronic device, such as a memory card, has a package structure in which a reduction in thickness is achieved while retaining the shielding effect and in which, if the device should be inserted incorrectly, no power source short-circuiting occurs without a mechanism for preventing incorrect insertion. The memory card 20 has a one-side-metal-plate type package structure and includes a plastic frame 11, a printed circuit board 12 which has a card contact edge section 14 for an input/output interface at an end thereof and on which semiconductor memory devices are mounted, and a metal panel 13. The plastic frame 11 is placed between the printed circuit board 12 and the metal plate 13. The distance D₁ between the card end surface 11a on that side of the card where the card contact edge section 14 is provided and the end 13a of the metal panel 13 on the same side of the card is set at a value that is larger than the distance A between the card end surface 11a on that side of the card where the card contact edge section 14 is provided and the contact position 8a of contact springs 8 of a card connector 7. If the memory card 20 is inserted in the reverse direction from the correct insertion direction, the contact sections 8a do not reach the metal panel 13, so that they are not brought into contact with the metal panel 13.

Claims

1. A card-type electronic device comprising:

a plastic frame enclosing an in-frame opening, said frame having a front end surface and a rear end surface, said rear end surface being remote from said front end surface;

a printed circuit board having an insertion end provided with a card contact edge section forming an input/output interface for connection to external contacts, said card contact edge section having a connector contact region for contacting the external contacts, said board carrying semiconductor devices and said insertion end facing toward said front end surface of said frame; and

a metal panel, said plastic frame being sandwiched between said printed circuit board and said metal panel, and said metal panel having a front edge facing toward said front end surface of said frame, wherein said front end surface of said frame is spaced at a distance D₁ from said front edge of said metal panel and at a distance A from said connector contact region of said printed circuit board, and A<

D₁.

2. A card-type electronic device according to claim 1, wherein said metal panel has a rear edge facing toward said rear end surface of said frame, said rear end surface of said frame is spaced at a distance D₂ from said rear edge of said metal panel, and A<

D₂.

3. A card-type electronic device according to claim 2 wherein said printed circuit board has a surface area and comprises a multilayer printed circuit, said printed circuit includes a surface conductive layer, said surface conductive layer has a first portion constituting said card contact edge section and a second portion constituting a grounding wiring pattern, and said first and second portions cover substantially the entirety of said surface area.

4. A card-type electronic device according to claim 3, wherein said printed circuit board has mutually perpendicular first and second dimensions and said grounding wiring pattern is provided with a plurality of first mutually parallel slits, each of said first slits having a length dimension which is oriented parallel to said first dimension of said printed circuit board.

5. A card-type electronic device according to claim 4, wherein said first slits are arranged in a plurality of mutually parallel rows, each row is parallel to said first dimension of said printed circuit board, and each said row is composed of a plurality of said first slits which are separated from one another by portions of said surface conductive layer.

6. A card-type electronic device according to claim 5, wherein:

said multilayer printed circuit further includes a power wiring pattern formed over substantially the entirety of said surface area as an internal conductive layer;

said power wiring pattern is provided with a plurality of second mutually parallel slits, each of said second slits having a length dimension which is oriented parallel to said second dimension of said printed circuit board;

said second slits are arranged in a plurality of mutually parallel rows, each row is parallel to said second dimension of said printed circuit board, and each said row is composed of a plurality of said second slits which are separated from one another by portions of said internal conductive layer.