Memory module

• US 6,343,020 B1
• Filed: 07/19/1999
• Issued: 01/29/2002
• Est. Priority Date: 12/28/1998
• Status: Expired due to Fees

• Current Assignee: Gold Charm Limited (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Foxconn Precision Component Company Limited (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Cheng, Nien-Tien, Liu, Heng-Chih, Lin, Pao-Lung
• Primary Examiner(s): Gaffin, Jeffrey
• Assistant Examiner(s): BUI, HUNG S
• Application Number:
  US09/356,481
• Time in Patent Office: 925 Days
• Field of Search: 361/816, 361/818, 361/684, 361/715, 361/794, 361/728, 361/801, 361/736, 361/704, 361/799, 361/753, 174/35.R, 174/50.G, 174/50.R, 439/607, 439/608, 439/609, 439/610
• US Class Current: 361/816
• CPC Class Codes: G11C 5/005 Circuit means for protection against loss of information of semiconductor storage devices
• CPC Class Codes: G11C 5/04 Supports for storage elements , e.g. memory modules; Mounting or fixing of storage elements on such supports

Abstract

A memory module includes a circuit board on which memory chips are mounted and a metal casing attached to the circuit board for shielding the memory chips. Conductive traces are formed on the circuit board for electrically engaging corresponding portions of the casing to ground the casing. The casing forms a raised portion defining a space for accommodating the memory chips. A recess is formed on the raised portion and a bottom surface of the recess contacts the memory chips to conduct and remove heat from the memory chips. Ventilation holes are defined in the raised portion for facilitating heat removal. The casing forms two positioning pins inserted into corresponding positioning holes defined in the circuit board for properly positioning the casing with respect to the circuit board. The casing also forms two latching arms engaging with corresponding latching holes defined in the circuit board for securing the casing to the circuit board.

Claims

1. A memory module comprising:

a circuit board on which memory chips are mounted, a plurality of latching holes being defined on the circuit board; and

a shielding casing comprising a flat plate mated with a face of the circuit board and a plurality of latching arms engaged with latching holes defined in the circuit board, thereby attaching the casing to the circuit board, the shielding casing forming a raised portion for defining a space to accommodate the memory chips therein, a recess being formed in the raised portion with a bottom surface thereof contacting the memory chips.

2. The memory module as claimed in claim 1, wherein at least one conductive grounding member is formed on the circuit board, the casing having a portion physically engaging with the grounding member of the circuit board for grounding the casing.

3. The memory module as claimed in claim 2, wherein the casing comprises an anodized metal member having a non-anodized portion for physically engaging the grounding member of the circuit board.

4. The memory module as claimed in claim 2, wherein the grounding member comprises a U-shaped conductive trace formed on the circuit board, the casing having two spaced portions engaging with corresponding limbs of the U-shaped conductive trace.

5. The memory module as claimed in claim 1, wherein the casing comprises two latching arms respectively engaging with two latching holes defined in the circuit board for securing the casing to the circuit board.

6. The memory module as claimed in claim 5, wherein a conductive grounding pad is formed on the circuit board around each latching hole, the casing having a portion adjacent to each latching arm for physically engaging with the corresponding grounding pad to ground the casing.

7. The memory module as claimed in claim 1, wherein ventilation holes are defined in the raised portion of the casing.

8. The memory module as claimed in claim 1, wherein the casing forms positioning pins thereon for insertion into corresponding positioning holes defined in the circuit board to properly position the casing with respect to the circuit board.

9. The memory module as claimed in claim 1, wherein the latching arms are stamped on the casing and comprise bent sections for engaging with the latching holes of the circuit board.

10. The memory module as claimed in claim 1, wherein the memory module is a RAM bus module.

11. A memory module comprising:

a circuit board on which a plurality of memory chips are mounted; and

a shielding casing having a similar planar dimension with the circuit board and attached thereto, and defining a raised portion enclosing therein said memory chips;

wherein

a bottom surface of the shielding casing contacts the chips for heat transfer consideration.

12. The memory module as claimed in claim 11, wherein a recess portion is formed in said raised portion, said raised portion defining a first height away from the circuit board, said recess defining a second height away from the circuit board, said second height being smaller than said first height.

13. The memory module as claimed in claim 12, wherein said bottom surface is formed on said recess portion.