Single Chip USB Packages By Various Assembly Methods

• US 20080020641A1
• Filed: 09/21/2007
• Published: 01/24/2008
• Est. Priority Date: 08/04/1999
• Status: Active Grant

• Current Assignee: Super Talent Technology, Corporation
• Original Assignee: Super Talent Electronics, Inc.
• Inventors: Shen, Ming-Shiang, Ni, Jim, Ma, Abraham, Hiew, Siew
• Granted Patent: US 7,447,037 B2
• Time in Patent Office: Days
• US Class Current: 439/607
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01024 Chromium [Cr]
• CPC Class Codes: H01L 2924/0103 Zinc [Zn]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01077 Iridium [Ir]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01R 13/665 with built-in electronic circuit H01R13/70, H01R13/719 take precedence
• CPC Class Codes: H05K 1/117 Pads along the edge of rigid circuit boards, e.g. for pluggable connectors
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: H05K 5/0278 : of USB type details relating to connectors H01R27/00

Abstract

A low-profile Universal-Serial-Bus (USB) assembly includes a modular USB core component and an external case. The modular USB core component includes a PCBA in which all passive components and unpackaged IC chips are attached to a single side of a PCB opposite to the metal contacts. The IC chips (e.g., USB controller, flash memory) are attached to the PCB by wire bonding or other chip-on-board (COB) technique. The passive components are attached by conventional surface mount technology (SMT) techniques. A molded housing is then formed over the IC chips and passive components such that the device has a uniform thickness. The modular USB core component is then inserted or otherwise combined with an external plastic case to provide a USB assembly. An optional carrying case is disclosed.

Claims

1. A USB assembly adapted to be accessed by a data terminal, said USB assembly comprising:

a modular USB core component comprising;

a PCBA including;

a card body,

a non-volatile memory device mounted on the card body,

a card reader interface circuit mounted on said card body, and

a processing unit mounted on said card body and connected to said non-volatile memory device and said card reader interface circuit,

wherein said card body comprises a printed circuit board (PCB) having opposing first and second surfaces, a plurality of metal contacts disposed on the first surface, at least one passive component mounted on the second surface,

wherein at least one of the non-volatile memory device, the card reader interface circuit and the processing unit comprises an unpackaged integrated circuit (IC) die mounted on the second surface of the PCB handle section, and

wherein a plurality of conductive traces are formed on the PCB such that each conductive trace is electrically connected to at least one of an associated metal contact, the IC die and the passive component; and

a single-piece molded housing formed on the second surface of the PCBA such that said at least one passive component and said at least one IC die are covered by said molded housing, and such that substantially all of the first surface of the PCB is exposed; and

a case fixedly connected to the modular USB core component such that the metal contacts are exposed through one or more openings defined by said case.

2. The USB assembly of claim 1, wherein the case comprises a single-piece, pre-molded plastic casing including a rear section and a front section, and wherein the modular USB core component is disposed in a cavity defined by the rear and front sections.

3. The USB assembly of claim 2, wherein the front section of the pre-molded plastic casing includes a plurality of ribs respectively separated by elongated openings, and wherein the modular USB core component is disposed in the cavity such that each of the plurality of metal contacts is exposed through a corresponding one of said plurality of elongated openings.

4. The USB assembly of claim 2, wherein the rear section of the pre-molded plastic casing defines an upper opening for insertion of the modular USB core component, and wherein the assembly further comprises a cover plate that is secured over the upper opening by one of a snap-coupling mechanism, a weld structure, an adhesive layer and a UV-cured epoxy adhesive.

5. The USB assembly of claim 1, wherein the case comprises a two-piece, pre-molded plastic casing including a lower case portion and an upper case portion mounted on the lower case portion, and wherein the modular USB core component is disposed in a cavity defined by the upper case portion and the lower case portion.

6. The USB assembly of claim 5, wherein the upper case portion includes a plurality of ribs respectively separated by elongated openings, and wherein the modular USB core component is disposed in the cavity such that each of the plurality of metal contacts is exposed through a corresponding one of said plurality of elongated openings.

7. The USB assembly of claim 5, wherein at least one of the upper case portion and the lower case portion are attached to the modular USB core component by way of an adhesive layer.

8. The USB assembly of claim 1, wherein the case comprises a bottom piece carrier defining a trough, and wherein the modular USB core component is disposed in the trough such that the metal contacts face away from the bottom piece carrier.

9. The USB assembly of claim 8, wherein the case further comprises one of a rear cap and a cover plate that is secured to the bottom piece carrier over a rear portion of the modular USB component.

10. The USB assembly of claim 1, wherein the case comprises an over-molded structure formed on the modular USB core component such that peripheral portions of the over-molded structure are disposed on the peripheral edges of the modular USB core component, and a lower wall portion of the over-molded structure is disposed on the lower surface of the modular USB core component, wherein the metal contacts of the modular USB core component face away from the over-molded structure.

11. The USB assembly of claim 10, wherein the case further comprises a pre-molded plastic cover having an upper wall and peripheral side walls defining a trough, wherein the upper wall defines a plurality of elongated openings, wherein the modular USB core component is mounted in trough such that each said metal contact is exposed through a corresponding one of said plurality of elongated openings, and wherein the peripheral portions of the over-molded structure are disposed between the peripheral edges of the modular USB core component and said peripheral side walls of the plastic cover.

12. The USB assembly of claim 1, further comprising a carrying case including a case body for securely holding the modular USB core component and the case such that the metal contacts are covered by a wall of the carrying case.

13. The USB assembly of claim 1, wherein the at least one integrated circuit (IC) die is electrically connected to the conductive traces by a plurality of wire bonds extending between said at least one IC die and corresponding contact pads disposed on the second surface of the PCB.

14. The USB assembly of claim 13, wherein the at least one passive component includes a lead that is soldered to a corresponding contact pad disposed on the second surface of the PCB.

15. The USB assembly of claim 14, wherein the at least one passive component comprises at least one of a resistor, a capacitor, an oscillator, and a light emitting diode.

16. The USB assembly of claim 13, wherein the at least one integrated circuit (IC) die includes a first IC die comprising an USB controller circuit, and a second IC die comprising a flash memory circuit.

17. The USB assembly of claim 16, wherein the at least one IC die comprises a plurality of flash memory dies disposed in a stacked arrangement such that a first flash memory die is mounted on the second surface of the PCB, and a second flash memory die is mounted on a surface of the first flash memory die.

18. The USB assembly of claim 17, wherein the first flash memory die is connected to said PCB by a first plurality of said wire bonds, and the second flash memory die is connected to one of the first flash memory die and said PCB by a second plurality of wire bonds.

19. The USB assembly of claim 13, wherein the at least one integrated circuit (IC) die includes a single-chip controller/flash die comprising controller circuit and one or more flash block mass storage circuits that are interconnected by a bus.

20. A method for producing an USB assembly comprising:

producing a modular USB core component including;

a PCBA including;

a cardbody,

a non-volatile memory device mounted on the card body,

a card reader interface circuit mounted on said card body, and

a processing unit mounted on said card body and connected to said non-volatile memory device and said card reader interface circuit,

wherein said card body comprises a printed circuit board (PCB) having opposing first and second surfaces, a plurality of metal contacts disposed on the first surface, at least one passive component mounted on the second surface,

wherein at least one of the non-volatile memory device, the card reader interface circuit and the processing unit comprises an unpackaged integrated circuit (IC) die mounted on the second surface of the PCB handle section, and

wherein a plurality of conductive traces are formed on the PCB such that each conductive trace is electrically connected to at least one of an associated metal contact, the IC die and the passive component; and

a single-piece molded housing formed on the second surface of the PCBA such that said at least one passive component and said at least one IC die are covered by said molded housing, and such that substantially all of the first surface of the PCB is exposed; and

mounting said modular USB core component into a case such that the case is fixedly connected to the modular USB core component with the metal contacts exposed through one or more openings defined by said case.